/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 sw=2 et tw=78: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
 * Base class for all our document implementations.
 */

#include "mozilla/DebugOnly.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Util.h"
#include "mozilla/Likely.h"
#include <algorithm>

#ifdef MOZ_LOGGING
// so we can get logging even in release builds
#define FORCE_PR_LOG 1
#endif
#include "prlog.h"
#include "plstr.h"
#include "prprf.h"

#include "mozilla/Telemetry.h"
#include "nsIInterfaceRequestor.h"
#include "nsIInterfaceRequestorUtils.h"
#include "nsDocument.h"
#include "nsUnicharUtils.h"
#include "nsContentList.h"
#include "nsIObserver.h"
#include "nsIBaseWindow.h"
#include "mozilla/css/Loader.h"
#include "mozilla/css/ImageLoader.h"
#include "nsIDocShell.h"
#include "nsIDocShellTreeItem.h"
#include "nsIScriptRuntime.h"
#include "nsCOMArray.h"
#include "nsDOMClassInfo.h"
#include "nsCxPusher.h"

#include "nsGUIEvent.h"
#include "nsAsyncDOMEvent.h"
#include "nsIDOMNodeFilter.h"

#include "nsIDOMStyleSheet.h"
#include "mozilla/dom/Attr.h"
#include "nsIDOMDOMStringList.h"
#include "nsIDOMDOMImplementation.h"
#include "nsIDOMDocumentXBL.h"
#include "mozilla/dom/Element.h"
#include "nsGenericHTMLElement.h"
#include "mozilla/dom/CDATASection.h"
#include "mozilla/dom/ProcessingInstruction.h"
#include "nsDOMString.h"
#include "nsNodeUtils.h"
#include "nsLayoutUtils.h" // for GetFrameForPoint
#include "nsIFrame.h"
#include "nsITabChild.h"

#include "nsRange.h"
#include "nsIDOMText.h"
#include "nsIDOMComment.h"
#include "mozilla/dom/DocumentType.h"
#include "mozilla/dom/NodeIterator.h"
#include "mozilla/dom/TreeWalker.h"

#include "nsIServiceManager.h"

#include "nsContentCID.h"
#include "nsError.h"
#include "nsPresShell.h"
#include "nsPresContext.h"
#include "nsIJSON.h"
#include "nsThreadUtils.h"
#include "nsNodeInfoManager.h"
#include "nsIFileChannel.h"
#include "nsIMultiPartChannel.h"
#include "nsIRefreshURI.h"
#include "nsIWebNavigation.h"
#include "nsIScriptError.h"
#include "nsStyleSheetService.h"

#include "nsNetUtil.h"     // for NS_MakeAbsoluteURI

#include "nsIScriptSecurityManager.h"
#include "nsIPrincipal.h"

#include "nsIDOMWindow.h"
#include "nsPIDOMWindow.h"
#include "nsIDOMElement.h"
#include "nsFocusManager.h"

// for radio group stuff
#include "nsIDOMHTMLInputElement.h"
#include "nsIRadioVisitor.h"
#include "nsIFormControl.h"

#include "nsBidiUtils.h"

#include "nsIDOMUserDataHandler.h"
#include "nsIDOMXPathEvaluator.h"
#include "nsIDOMXPathExpression.h"
#include "nsIDOMXPathNSResolver.h"
#include "nsIXPathEvaluatorInternal.h"
#include "nsIParserService.h"
#include "nsContentCreatorFunctions.h"

#include "nsIScriptContext.h"
#include "nsBindingManager.h"
#include "nsIDOMHTMLDocument.h"
#include "nsHTMLDocument.h"
#include "nsIDOMHTMLFormElement.h"
#include "nsIRequest.h"
#include "nsILink.h"
#include "nsHostObjectProtocolHandler.h"

#include "nsCharsetAlias.h"
#include "nsCharsetSource.h"
#include "nsIParser.h"
#include "nsIContentSink.h"

#include "nsDateTimeFormatCID.h"
#include "nsIDateTimeFormat.h"
#include "nsEventDispatcher.h"
#include "nsMutationEvent.h"
#include "nsDOMCID.h"

#include "jsapi.h"
#include "nsIXPConnect.h"
#include "nsCCUncollectableMarker.h"
#include "nsIContentPolicy.h"
#include "nsContentPolicyUtils.h"
#include "nsICategoryManager.h"
#include "nsIDocumentLoaderFactory.h"
#include "nsIDocumentLoader.h"
#include "nsIContentViewer.h"
#include "nsIXMLContentSink.h"
#include "nsIXULDocument.h"
#include "nsIPrompt.h"
#include "nsIPropertyBag2.h"
#include "nsIDOMPageTransitionEvent.h"
#include "nsIDOMStyleRuleChangeEvent.h"
#include "nsIDOMStyleSheetChangeEvent.h"
#include "nsIDOMStyleSheetApplicableStateChangeEvent.h"
#include "nsJSUtils.h"
#include "nsFrameLoader.h"
#include "nsEscape.h"
#include "nsObjectLoadingContent.h"
#include "nsHtml5TreeOpExecutor.h"
#include "nsIDOMElementReplaceEvent.h"
#include "mozilla/dom/HTMLMediaElement.h"
#ifdef MOZ_WEBRTC
#include "IPeerConnection.h"
#endif // MOZ_WEBRTC

#include "mozAutoDocUpdate.h"
#include "nsGlobalWindow.h"
#include "mozilla/dom/EncodingUtils.h"
#include "mozilla/dom/quota/QuotaManager.h"
#include "nsDOMNavigationTiming.h"
#include "nsEventStateManager.h"

#include "nsSMILAnimationController.h"
#include "imgIContainer.h"
#include "nsSVGUtils.h"

#include "nsRefreshDriver.h"

// FOR CSP (autogenerated by xpidl)
#include "nsIContentSecurityPolicy.h"
#include "nsCSPService.h"
#include "nsHTMLStyleSheet.h"
#include "nsHTMLCSSStyleSheet.h"
#include "mozilla/dom/DOMImplementation.h"
#include "mozilla/dom/Comment.h"
#include "nsTextNode.h"
#include "mozilla/dom/Link.h"
#include "mozilla/dom/HTMLElementBinding.h"
#include "nsXULAppAPI.h"
#include "nsDOMTouchEvent.h"
#include "mozilla/dom/Touch.h"
#include "DictionaryHelpers.h"
#include "GeneratedEvents.h"

#include "mozilla/Preferences.h"

#include "imgILoader.h"
#include "imgRequestProxy.h"
#include "nsWrapperCacheInlines.h"
#include "nsSandboxFlags.h"
#include "nsIAppsService.h"
#include "mozilla/dom/BindingUtils.h"
#include "mozilla/dom/DocumentFragment.h"
#include "mozilla/dom/WebComponentsBinding.h"
#include "mozilla/dom/HTMLBodyElement.h"
#include "mozilla/dom/NodeFilterBinding.h"
#include "mozilla/dom/UndoManager.h"
#include "nsFrame.h"
#include "nsDOMCaretPosition.h"
#include "nsIDOMHTMLTextAreaElement.h"
#include "nsViewportInfo.h"
#include "nsDOMEvent.h"
#include "nsIContentPermissionPrompt.h"
#include "mozilla/StaticPtr.h"
#include "nsITextControlElement.h"
#include "nsIDOMNSEditableElement.h"
#include "nsIEditor.h"
#include "nsIDOMCSSStyleRule.h"
#include "mozilla/css/Rule.h"

using namespace mozilla;
using namespace mozilla::dom;

typedef nsTArray<Link*> LinkArray;

#ifdef PR_LOGGING
static PRLogModuleInfo* gDocumentLeakPRLog;
static PRLogModuleInfo* gCspPRLog;
#endif

#define NAME_NOT_VALID ((nsSimpleContentList*)1)

nsIdentifierMapEntry::~nsIdentifierMapEntry()
{
}

void
nsIdentifierMapEntry::Traverse(nsCycleCollectionTraversalCallback* aCallback)
{
  NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*aCallback,
                                     "mIdentifierMap mNameContentList");
  aCallback->NoteXPCOMChild(static_cast<nsIDOMNodeList*>(mNameContentList));

  NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*aCallback, "mIdentifierMap mDocAllList");
  aCallback->NoteXPCOMChild(static_cast<nsIDOMNodeList*>(mDocAllList));

  if (mImageElement) {
    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*aCallback,
                                       "mIdentifierMap mImageElement element");
    nsIContent* imageElement = mImageElement;
    aCallback->NoteXPCOMChild(imageElement);
  }
}

bool
nsIdentifierMapEntry::IsEmpty()
{
  return mIdContentList.Count() == 0 && !mNameContentList &&
         !mChangeCallbacks && !mImageElement;
}

Element*
nsIdentifierMapEntry::GetIdElement()
{
  return static_cast<Element*>(mIdContentList.SafeElementAt(0));
}

Element*
nsIdentifierMapEntry::GetImageIdElement()
{
  return mImageElement ? mImageElement.get() : GetIdElement();
}

void
nsIdentifierMapEntry::AppendAllIdContent(nsCOMArray<nsIContent>* aElements)
{
  for (int32_t i = 0; i < mIdContentList.Count(); ++i) {
    aElements->AppendObject(static_cast<Element*>(mIdContentList[i]));
  }
}

void
nsIdentifierMapEntry::AddContentChangeCallback(nsIDocument::IDTargetObserver aCallback,
                                               void* aData, bool aForImage)
{
  if (!mChangeCallbacks) {
    mChangeCallbacks = new nsTHashtable<ChangeCallbackEntry>;
    if (!mChangeCallbacks)
      return;
    mChangeCallbacks->Init();
  }

  ChangeCallback cc = { aCallback, aData, aForImage };
  mChangeCallbacks->PutEntry(cc);
}

void
nsIdentifierMapEntry::RemoveContentChangeCallback(nsIDocument::IDTargetObserver aCallback,
                                                  void* aData, bool aForImage)
{
  if (!mChangeCallbacks)
    return;
  ChangeCallback cc = { aCallback, aData, aForImage };
  mChangeCallbacks->RemoveEntry(cc);
  if (mChangeCallbacks->Count() == 0) {
    mChangeCallbacks = nullptr;
  }
}

struct FireChangeArgs {
  Element* mFrom;
  Element* mTo;
  bool mImageOnly;
  bool mHaveImageOverride;
};

static PLDHashOperator
FireChangeEnumerator(nsIdentifierMapEntry::ChangeCallbackEntry *aEntry, void *aArg)
{
  FireChangeArgs* args = static_cast<FireChangeArgs*>(aArg);
  // Don't fire image changes for non-image observers, and don't fire element
  // changes for image observers when an image override is active.
  if (aEntry->mKey.mForImage ? (args->mHaveImageOverride && !args->mImageOnly) :
                               args->mImageOnly)
    return PL_DHASH_NEXT;
  return aEntry->mKey.mCallback(args->mFrom, args->mTo, aEntry->mKey.mData)
      ? PL_DHASH_NEXT : PL_DHASH_REMOVE;
}

void
nsIdentifierMapEntry::FireChangeCallbacks(Element* aOldElement,
                                          Element* aNewElement,
                                          bool aImageOnly)
{
  if (!mChangeCallbacks)
    return;

  FireChangeArgs args = { aOldElement, aNewElement, aImageOnly, !!mImageElement };
  mChangeCallbacks->EnumerateEntries(FireChangeEnumerator, &args);
}

bool
nsIdentifierMapEntry::AddIdElement(Element* aElement)
{
  NS_PRECONDITION(aElement, "Must have element");
  NS_PRECONDITION(mIdContentList.IndexOf(nullptr) < 0,
                  "Why is null in our list?");

#ifdef DEBUG
  Element* currentElement =
    static_cast<Element*>(mIdContentList.SafeElementAt(0));
#endif

  // Common case
  if (mIdContentList.Count() == 0) {
    if (!mIdContentList.AppendElement(aElement))
      return false;
    NS_ASSERTION(currentElement == nullptr, "How did that happen?");
    FireChangeCallbacks(nullptr, aElement);
    return true;
  }

  // We seem to have multiple content nodes for the same id, or XUL is messing
  // with us.  Search for the right place to insert the content.
  int32_t start = 0;
  int32_t end = mIdContentList.Count();
  do {
    NS_ASSERTION(start < end, "Bogus start/end");

    int32_t cur = (start + end) / 2;
    NS_ASSERTION(cur >= start && cur < end, "What happened here?");

    Element* curElement = static_cast<Element*>(mIdContentList[cur]);
    if (curElement == aElement) {
      // Already in the list, so already in the right spot.  Get out of here.
      // XXXbz this only happens because XUL does all sorts of random
      // UpdateIdTableEntry calls.  Hate, hate, hate!
      return true;
    }

    if (nsContentUtils::PositionIsBefore(aElement, curElement)) {
      end = cur;
    } else {
      start = cur + 1;
    }
  } while (start != end);

  if (!mIdContentList.InsertElementAt(aElement, start))
    return false;

  if (start == 0) {
    Element* oldElement =
      static_cast<Element*>(mIdContentList.SafeElementAt(1));
    NS_ASSERTION(currentElement == oldElement, "How did that happen?");
    FireChangeCallbacks(oldElement, aElement);
  }
  return true;
}

void
nsIdentifierMapEntry::RemoveIdElement(Element* aElement)
{
  NS_PRECONDITION(aElement, "Missing element");

  // This should only be called while the document is in an update.
  // Assertions near the call to this method guarantee this.

  // This could fire in OOM situations
  // Only assert this in HTML documents for now as XUL does all sorts of weird
  // crap.
  NS_ASSERTION(!aElement->OwnerDoc()->IsHTML() ||
               mIdContentList.IndexOf(aElement) >= 0,
               "Removing id entry that doesn't exist");

  // XXXbz should this ever Compact() I guess when all the content is gone
  // we'll just get cleaned up in the natural order of things...
  Element* currentElement =
    static_cast<Element*>(mIdContentList.SafeElementAt(0));
  mIdContentList.RemoveElement(aElement);
  if (currentElement == aElement) {
    FireChangeCallbacks(currentElement,
                        static_cast<Element*>(mIdContentList.SafeElementAt(0)));
  }
}

void
nsIdentifierMapEntry::SetImageElement(Element* aElement)
{
  Element* oldElement = GetImageIdElement();
  mImageElement = aElement;
  Element* newElement = GetImageIdElement();
  if (oldElement != newElement) {
    FireChangeCallbacks(oldElement, newElement, true);
  }
}

void
nsIdentifierMapEntry::AddNameElement(nsIDocument* aDocument, Element* aElement)
{
  if (!mNameContentList) {
    mNameContentList = new nsSimpleContentList(aDocument);
  }

  mNameContentList->AppendElement(aElement);
}

void
nsIdentifierMapEntry::RemoveNameElement(Element* aElement)
{
  if (mNameContentList) {
    mNameContentList->RemoveElement(aElement);
  }
}

bool
nsIdentifierMapEntry::HasIdElementExposedAsHTMLDocumentProperty()
{
  Element* idElement = GetIdElement();
  return idElement &&
         nsGenericHTMLElement::ShouldExposeIdAsHTMLDocumentProperty(idElement);
}

// static
size_t
nsIdentifierMapEntry::SizeOfExcludingThis(nsIdentifierMapEntry* aEntry,
                                          MallocSizeOf aMallocSizeOf,
                                          void*)
{
  return aEntry->GetKey().SizeOfExcludingThisIfUnshared(aMallocSizeOf);
}

// Helper structs for the content->subdoc map

class SubDocMapEntry : public PLDHashEntryHdr
{
public:
  // Both of these are strong references
  Element *mKey; // must be first, to look like PLDHashEntryStub
  nsIDocument *mSubDocument;
};

struct FindContentData
{
  FindContentData(nsIDocument *aSubDoc)
    : mSubDocument(aSubDoc), mResult(nullptr)
  {
  }

  nsISupports *mSubDocument;
  Element *mResult;
};


/**
 * A struct that holds all the information about a radio group.
 */
struct nsRadioGroupStruct
{
  nsRadioGroupStruct()
    : mRequiredRadioCount(0)
    , mGroupSuffersFromValueMissing(false)
  {}

  /**
   * A strong pointer to the currently selected radio button.
   */
  nsCOMPtr<nsIDOMHTMLInputElement> mSelectedRadioButton;
  nsCOMArray<nsIFormControl> mRadioButtons;
  uint32_t mRequiredRadioCount;
  bool mGroupSuffersFromValueMissing;
};


nsDOMStyleSheetList::nsDOMStyleSheetList(nsIDocument *aDocument)
{
  mLength = -1;
  // Not reference counted to avoid circular references.
  // The document will tell us when its going away.
  mDocument = aDocument;
  mDocument->AddObserver(this);
}

nsDOMStyleSheetList::~nsDOMStyleSheetList()
{
  if (mDocument) {
    mDocument->RemoveObserver(this);
  }
}

DOMCI_DATA(StyleSheetList, nsDOMStyleSheetList)

// XXX couldn't we use the GetIIDs method from CSSStyleSheetList here?
// QueryInterface implementation for nsDOMStyleSheetList
NS_INTERFACE_TABLE_HEAD(nsDOMStyleSheetList)
  NS_INTERFACE_TABLE3(nsDOMStyleSheetList,
                      nsIDOMStyleSheetList,
                      nsIDocumentObserver,
                      nsIMutationObserver)
  NS_INTERFACE_TABLE_TO_MAP_SEGUE
  NS_DOM_INTERFACE_MAP_ENTRY_CLASSINFO(StyleSheetList)
NS_INTERFACE_MAP_END


NS_IMPL_ADDREF(nsDOMStyleSheetList)
NS_IMPL_RELEASE(nsDOMStyleSheetList)


NS_IMETHODIMP
nsDOMStyleSheetList::GetLength(uint32_t* aLength)
{
  if (mDocument) {
    // XXX Find the number and then cache it. We'll use the
    // observer notification to figure out if new ones have
    // been added or removed.
    if (-1 == mLength) {
      mLength = mDocument->GetNumberOfStyleSheets();

#ifdef DEBUG
      int32_t i;
      for (i = 0; i < mLength; i++) {
        nsIStyleSheet *sheet = mDocument->GetStyleSheetAt(i);
        nsCOMPtr<nsIDOMStyleSheet> domss(do_QueryInterface(sheet));
        NS_ASSERTION(domss, "All \"normal\" sheets implement nsIDOMStyleSheet");
      }
#endif
    }
    *aLength = mLength;
  }
  else {
    *aLength = 0;
  }

  return NS_OK;
}

nsIStyleSheet*
nsDOMStyleSheetList::GetItemAt(uint32_t aIndex)
{
  if (!mDocument || aIndex >= (uint32_t)mDocument->GetNumberOfStyleSheets()) {
    return nullptr;
  }

  nsIStyleSheet *sheet = mDocument->GetStyleSheetAt(aIndex);
  NS_ASSERTION(sheet, "Must have a sheet");

  return sheet;
}

NS_IMETHODIMP
nsDOMStyleSheetList::Item(uint32_t aIndex, nsIDOMStyleSheet** aReturn)
{
  nsIStyleSheet *sheet = GetItemAt(aIndex);
  if (!sheet) {
      *aReturn = nullptr;

      return NS_OK;
  }

  return CallQueryInterface(sheet, aReturn);
}

void
nsDOMStyleSheetList::NodeWillBeDestroyed(const nsINode *aNode)
{
  mDocument = nullptr;
}

void
nsDOMStyleSheetList::StyleSheetAdded(nsIDocument *aDocument,
                                     nsIStyleSheet* aStyleSheet,
                                     bool aDocumentSheet)
{
  if (aDocumentSheet && -1 != mLength) {
    nsCOMPtr<nsIDOMStyleSheet> domss(do_QueryInterface(aStyleSheet));
    if (domss) {
      mLength++;
    }
  }
}

void
nsDOMStyleSheetList::StyleSheetRemoved(nsIDocument *aDocument,
                                       nsIStyleSheet* aStyleSheet,
                                       bool aDocumentSheet)
{
  if (aDocumentSheet && -1 != mLength) {
    nsCOMPtr<nsIDOMStyleSheet> domss(do_QueryInterface(aStyleSheet));
    if (domss) {
      mLength--;
    }
  }
}

// nsOnloadBlocker implementation
NS_IMPL_ISUPPORTS1(nsOnloadBlocker, nsIRequest)

NS_IMETHODIMP
nsOnloadBlocker::GetName(nsACString &aResult)
{
  aResult.AssignLiteral("about:document-onload-blocker");
  return NS_OK;
}

NS_IMETHODIMP
nsOnloadBlocker::IsPending(bool *_retval)
{
  *_retval = true;
  return NS_OK;
}

NS_IMETHODIMP
nsOnloadBlocker::GetStatus(nsresult *status)
{
  *status = NS_OK;
  return NS_OK;
}

NS_IMETHODIMP
nsOnloadBlocker::Cancel(nsresult status)
{
  return NS_OK;
}
NS_IMETHODIMP
nsOnloadBlocker::Suspend(void)
{
  return NS_OK;
}
NS_IMETHODIMP
nsOnloadBlocker::Resume(void)
{
  return NS_OK;
}

NS_IMETHODIMP
nsOnloadBlocker::GetLoadGroup(nsILoadGroup * *aLoadGroup)
{
  *aLoadGroup = nullptr;
  return NS_OK;
}

NS_IMETHODIMP
nsOnloadBlocker::SetLoadGroup(nsILoadGroup * aLoadGroup)
{
  return NS_OK;
}

NS_IMETHODIMP
nsOnloadBlocker::GetLoadFlags(nsLoadFlags *aLoadFlags)
{
  *aLoadFlags = nsIRequest::LOAD_NORMAL;
  return NS_OK;
}

NS_IMETHODIMP
nsOnloadBlocker::SetLoadFlags(nsLoadFlags aLoadFlags)
{
  return NS_OK;
}

// ==================================================================

nsExternalResourceMap::nsExternalResourceMap()
  : mHaveShutDown(false)
{
  mMap.Init();
  mPendingLoads.Init();
}

nsIDocument*
nsExternalResourceMap::RequestResource(nsIURI* aURI,
                                       nsINode* aRequestingNode,
                                       nsDocument* aDisplayDocument,
                                       ExternalResourceLoad** aPendingLoad)
{
  // If we ever start allowing non-same-origin loads here, we might need to do
  // something interesting with aRequestingPrincipal even for the hashtable
  // gets.
  NS_PRECONDITION(aURI, "Must have a URI");
  NS_PRECONDITION(aRequestingNode, "Must have a node");
  *aPendingLoad = nullptr;
  if (mHaveShutDown) {
    return nullptr;
  }

  // First, make sure we strip the ref from aURI.
  nsCOMPtr<nsIURI> clone;
  nsresult rv = aURI->CloneIgnoringRef(getter_AddRefs(clone));
  if (NS_FAILED(rv) || !clone) {
    return nullptr;
  }

  ExternalResource* resource;
  mMap.Get(clone, &resource);
  if (resource) {
    return resource->mDocument;
  }

  nsRefPtr<PendingLoad> load;
  mPendingLoads.Get(clone, getter_AddRefs(load));
  if (load) {
    load.forget(aPendingLoad);
    return nullptr;
  }

  load = new PendingLoad(aDisplayDocument);

  mPendingLoads.Put(clone, load);

  if (NS_FAILED(load->StartLoad(clone, aRequestingNode))) {
    // Make sure we don't thrash things by trying this load again, since
    // chances are it failed for good reasons (security check, etc).
    AddExternalResource(clone, nullptr, nullptr, aDisplayDocument);
  } else {
    load.forget(aPendingLoad);
  }

  return nullptr;
}

struct
nsExternalResourceEnumArgs
{
  nsIDocument::nsSubDocEnumFunc callback;
  void *data;
};

static PLDHashOperator
ExternalResourceEnumerator(nsIURI* aKey,
                           nsExternalResourceMap::ExternalResource* aData,
                           void* aClosure)
{
  nsExternalResourceEnumArgs* args =
    static_cast<nsExternalResourceEnumArgs*>(aClosure);
  bool next =
    aData->mDocument ? args->callback(aData->mDocument, args->data) : true;
  return next ? PL_DHASH_NEXT : PL_DHASH_STOP;
}

void
nsExternalResourceMap::EnumerateResources(nsIDocument::nsSubDocEnumFunc aCallback,
                                          void* aData)
{
  nsExternalResourceEnumArgs args = { aCallback, aData };
  mMap.EnumerateRead(ExternalResourceEnumerator, &args);
}

static PLDHashOperator
ExternalResourceTraverser(nsIURI* aKey,
                          nsExternalResourceMap::ExternalResource* aData,
                          void* aClosure)
{
  nsCycleCollectionTraversalCallback *cb =
    static_cast<nsCycleCollectionTraversalCallback*>(aClosure);

  NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*cb,
                                     "mExternalResourceMap.mMap entry"
                                     "->mDocument");
  cb->NoteXPCOMChild(aData->mDocument);

  NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*cb,
                                     "mExternalResourceMap.mMap entry"
                                     "->mViewer");
  cb->NoteXPCOMChild(aData->mViewer);

  NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*cb,
                                     "mExternalResourceMap.mMap entry"
                                     "->mLoadGroup");
  cb->NoteXPCOMChild(aData->mLoadGroup);

  return PL_DHASH_NEXT;
}

void
nsExternalResourceMap::Traverse(nsCycleCollectionTraversalCallback* aCallback) const
{
  // mPendingLoads will get cleared out as the requests complete, so
  // no need to worry about those here.
  mMap.EnumerateRead(ExternalResourceTraverser, aCallback);
}

static PLDHashOperator
ExternalResourceHider(nsIURI* aKey,
                      nsExternalResourceMap::ExternalResource* aData,
                      void* aClosure)
{
  if (aData->mViewer) {
    aData->mViewer->Hide();
  }
  return PL_DHASH_NEXT;
}

void
nsExternalResourceMap::HideViewers()
{
  mMap.EnumerateRead(ExternalResourceHider, nullptr);
}

static PLDHashOperator
ExternalResourceShower(nsIURI* aKey,
                       nsExternalResourceMap::ExternalResource* aData,
                       void* aClosure)
{
  if (aData->mViewer) {
    aData->mViewer->Show();
  }
  return PL_DHASH_NEXT;
}

void
nsExternalResourceMap::ShowViewers()
{
  mMap.EnumerateRead(ExternalResourceShower, nullptr);
}

void
TransferZoomLevels(nsIDocument* aFromDoc,
                   nsIDocument* aToDoc)
{
  NS_ABORT_IF_FALSE(aFromDoc && aToDoc,
                    "transferring zoom levels from/to null doc");

  nsIPresShell* fromShell = aFromDoc->GetShell();
  if (!fromShell)
    return;

  nsPresContext* fromCtxt = fromShell->GetPresContext();
  if (!fromCtxt)
    return;

  nsIPresShell* toShell = aToDoc->GetShell();
  if (!toShell)
    return;

  nsPresContext* toCtxt = toShell->GetPresContext();
  if (!toCtxt)
    return;

  toCtxt->SetFullZoom(fromCtxt->GetFullZoom());
  toCtxt->SetMinFontSize(fromCtxt->MinFontSize(nullptr));
  toCtxt->SetTextZoom(fromCtxt->TextZoom());
}

void
TransferShowingState(nsIDocument* aFromDoc, nsIDocument* aToDoc)
{
  NS_ABORT_IF_FALSE(aFromDoc && aToDoc,
                    "transferring showing state from/to null doc");

  if (aFromDoc->IsShowing()) {
    aToDoc->OnPageShow(true, nullptr);
  }
}

nsresult
nsExternalResourceMap::AddExternalResource(nsIURI* aURI,
                                           nsIContentViewer* aViewer,
                                           nsILoadGroup* aLoadGroup,
                                           nsIDocument* aDisplayDocument)
{
  NS_PRECONDITION(aURI, "Unexpected call");
  NS_PRECONDITION((aViewer && aLoadGroup) || (!aViewer && !aLoadGroup),
                  "Must have both or neither");

  nsRefPtr<PendingLoad> load;
  mPendingLoads.Get(aURI, getter_AddRefs(load));
  mPendingLoads.Remove(aURI);

  nsresult rv = NS_OK;

  nsCOMPtr<nsIDocument> doc;
  if (aViewer) {
    doc = aViewer->GetDocument();
    NS_ASSERTION(doc, "Must have a document");

    nsCOMPtr<nsIXULDocument> xulDoc = do_QueryInterface(doc);
    if (xulDoc) {
      // We don't handle XUL stuff here yet.
      rv = NS_ERROR_NOT_AVAILABLE;
    } else {
      doc->SetDisplayDocument(aDisplayDocument);

      // Make sure that hiding our viewer will tear down its presentation.
      aViewer->SetSticky(false);

      rv = aViewer->Init(nullptr, nsIntRect(0, 0, 0, 0));
      if (NS_SUCCEEDED(rv)) {
        rv = aViewer->Open(nullptr, nullptr);
      }
    }

    if (NS_FAILED(rv)) {
      doc = nullptr;
      aViewer = nullptr;
      aLoadGroup = nullptr;
    }
  }

  ExternalResource* newResource = new ExternalResource();
  mMap.Put(aURI, newResource);

  newResource->mDocument = doc;
  newResource->mViewer = aViewer;
  newResource->mLoadGroup = aLoadGroup;
  if (doc) {
    TransferZoomLevels(aDisplayDocument, doc);
    TransferShowingState(aDisplayDocument, doc);
  }

  const nsTArray< nsCOMPtr<nsIObserver> > & obs = load->Observers();
  for (uint32_t i = 0; i < obs.Length(); ++i) {
    obs[i]->Observe(doc, "external-resource-document-created", nullptr);
  }

  return rv;
}

NS_IMPL_ISUPPORTS2(nsExternalResourceMap::PendingLoad,
                   nsIStreamListener,
                   nsIRequestObserver)

NS_IMETHODIMP
nsExternalResourceMap::PendingLoad::OnStartRequest(nsIRequest *aRequest,
                                                   nsISupports *aContext)
{
  nsExternalResourceMap& map = mDisplayDocument->ExternalResourceMap();
  if (map.HaveShutDown()) {
    return NS_BINDING_ABORTED;
  }

  nsCOMPtr<nsIContentViewer> viewer;
  nsCOMPtr<nsILoadGroup> loadGroup;
  nsresult rv = SetupViewer(aRequest, getter_AddRefs(viewer),
                            getter_AddRefs(loadGroup));

  // Make sure to do this no matter what
  nsresult rv2 = map.AddExternalResource(mURI, viewer, loadGroup,
                                         mDisplayDocument);
  if (NS_FAILED(rv)) {
    return rv;
  }
  if (NS_FAILED(rv2)) {
    mTargetListener = nullptr;
    return rv2;
  }

  return mTargetListener->OnStartRequest(aRequest, aContext);
}

nsresult
nsExternalResourceMap::PendingLoad::SetupViewer(nsIRequest* aRequest,
                                                nsIContentViewer** aViewer,
                                                nsILoadGroup** aLoadGroup)
{
  NS_PRECONDITION(!mTargetListener, "Unexpected call to OnStartRequest");
  *aViewer = nullptr;
  *aLoadGroup = nullptr;

  nsCOMPtr<nsIChannel> chan(do_QueryInterface(aRequest));
  NS_ENSURE_TRUE(chan, NS_ERROR_UNEXPECTED);

  nsCOMPtr<nsIHttpChannel> httpChannel(do_QueryInterface(aRequest));
  if (httpChannel) {
    bool requestSucceeded;
    if (NS_FAILED(httpChannel->GetRequestSucceeded(&requestSucceeded)) ||
        !requestSucceeded) {
      // Bail out on this load, since it looks like we have an HTTP error page
      return NS_BINDING_ABORTED;
    }
  }

  nsAutoCString type;
  chan->GetContentType(type);

  nsCOMPtr<nsILoadGroup> loadGroup;
  chan->GetLoadGroup(getter_AddRefs(loadGroup));

  // Give this document its own loadgroup
  nsCOMPtr<nsILoadGroup> newLoadGroup =
        do_CreateInstance(NS_LOADGROUP_CONTRACTID);
  NS_ENSURE_TRUE(newLoadGroup, NS_ERROR_OUT_OF_MEMORY);
  newLoadGroup->SetLoadGroup(loadGroup);

  nsCOMPtr<nsIInterfaceRequestor> callbacks;
  loadGroup->GetNotificationCallbacks(getter_AddRefs(callbacks));

  nsCOMPtr<nsIInterfaceRequestor> newCallbacks =
    new LoadgroupCallbacks(callbacks);
  newLoadGroup->SetNotificationCallbacks(newCallbacks);

  // This is some serious hackery cribbed from docshell
  nsCOMPtr<nsICategoryManager> catMan =
    do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
  NS_ENSURE_TRUE(catMan, NS_ERROR_NOT_AVAILABLE);
  nsXPIDLCString contractId;
  nsresult rv = catMan->GetCategoryEntry("Gecko-Content-Viewers", type.get(),
                                         getter_Copies(contractId));
  NS_ENSURE_SUCCESS(rv, rv);
  nsCOMPtr<nsIDocumentLoaderFactory> docLoaderFactory =
    do_GetService(contractId);
  NS_ENSURE_TRUE(docLoaderFactory, NS_ERROR_NOT_AVAILABLE);

  nsCOMPtr<nsIContentViewer> viewer;
  nsCOMPtr<nsIStreamListener> listener;
  rv = docLoaderFactory->CreateInstance("external-resource", chan, newLoadGroup,
                                        type.get(), nullptr, nullptr,
                                        getter_AddRefs(listener),
                                        getter_AddRefs(viewer));
  NS_ENSURE_SUCCESS(rv, rv);
  NS_ENSURE_TRUE(viewer, NS_ERROR_UNEXPECTED);

  nsCOMPtr<nsIParser> parser = do_QueryInterface(listener);
  if (!parser) {
    /// We don't want to deal with the various fake documents yet
    return NS_ERROR_NOT_IMPLEMENTED;
  }

  // We can't handle HTML and other weird things here yet.
  nsIContentSink* sink = parser->GetContentSink();
  nsCOMPtr<nsIXMLContentSink> xmlSink = do_QueryInterface(sink);
  if (!xmlSink) {
    return NS_ERROR_NOT_IMPLEMENTED;
  }

  listener.swap(mTargetListener);
  viewer.forget(aViewer);
  newLoadGroup.forget(aLoadGroup);
  return NS_OK;
}

NS_IMETHODIMP
nsExternalResourceMap::PendingLoad::OnDataAvailable(nsIRequest* aRequest,
                                                    nsISupports* aContext,
                                                    nsIInputStream* aStream,
                                                    uint64_t aOffset,
                                                    uint32_t aCount)
{
  NS_PRECONDITION(mTargetListener, "Shouldn't be getting called!");
  if (mDisplayDocument->ExternalResourceMap().HaveShutDown()) {
    return NS_BINDING_ABORTED;
  }
  return mTargetListener->OnDataAvailable(aRequest, aContext, aStream, aOffset,
                                          aCount);
}

NS_IMETHODIMP
nsExternalResourceMap::PendingLoad::OnStopRequest(nsIRequest* aRequest,
                                                  nsISupports* aContext,
                                                  nsresult aStatus)
{
  // mTargetListener might be null if SetupViewer or AddExternalResource failed
  if (mTargetListener) {
    nsCOMPtr<nsIStreamListener> listener;
    mTargetListener.swap(listener);
    return listener->OnStopRequest(aRequest, aContext, aStatus);
  }

  return NS_OK;
}

nsresult
nsExternalResourceMap::PendingLoad::StartLoad(nsIURI* aURI,
                                              nsINode* aRequestingNode)
{
  NS_PRECONDITION(aURI, "Must have a URI");
  NS_PRECONDITION(aRequestingNode, "Must have a node");

  // Time to start a load.  First, the security checks.

  nsIPrincipal* requestingPrincipal = aRequestingNode->NodePrincipal();

  nsresult rv = nsContentUtils::GetSecurityManager()->
    CheckLoadURIWithPrincipal(requestingPrincipal, aURI,
                              nsIScriptSecurityManager::STANDARD);
  NS_ENSURE_SUCCESS(rv, rv);

  // Allow data URIs and other URI's that inherit their principal by passing
  // true as the 3rd argument of CheckMayLoad, since we want
  // to allow external resources from data URIs regardless of the difference
  // in URI scheme.
  rv = requestingPrincipal->CheckMayLoad(aURI, true, true);
  NS_ENSURE_SUCCESS(rv, rv);

  int16_t shouldLoad = nsIContentPolicy::ACCEPT;
  rv = NS_CheckContentLoadPolicy(nsIContentPolicy::TYPE_OTHER,
                                 aURI,
                                 requestingPrincipal,
                                 aRequestingNode,
                                 EmptyCString(), //mime guess
                                 nullptr,         //extra
                                 &shouldLoad,
                                 nsContentUtils::GetContentPolicy(),
                                 nsContentUtils::GetSecurityManager());
  if (NS_FAILED(rv)) return rv;
  if (NS_CP_REJECTED(shouldLoad)) {
    // Disallowed by content policy
    return NS_ERROR_CONTENT_BLOCKED;
  }

  nsIDocument* doc = aRequestingNode->OwnerDoc();

  nsCOMPtr<nsIInterfaceRequestor> req = nsContentUtils::GetSameOriginChecker();
  NS_ENSURE_TRUE(req, NS_ERROR_OUT_OF_MEMORY);

  nsCOMPtr<nsILoadGroup> loadGroup = doc->GetDocumentLoadGroup();
  nsCOMPtr<nsIChannel> channel;
  rv = NS_NewChannel(getter_AddRefs(channel), aURI, nullptr, loadGroup, req);
  NS_ENSURE_SUCCESS(rv, rv);

  mURI = aURI;

  return channel->AsyncOpen(this, nullptr);
}

NS_IMPL_ISUPPORTS1(nsExternalResourceMap::LoadgroupCallbacks,
                   nsIInterfaceRequestor)

#define IMPL_SHIM(_i) \
  NS_IMPL_ISUPPORTS1(nsExternalResourceMap::LoadgroupCallbacks::_i##Shim, _i)

IMPL_SHIM(nsILoadContext)
IMPL_SHIM(nsIProgressEventSink)
IMPL_SHIM(nsIChannelEventSink)
IMPL_SHIM(nsISecurityEventSink)
IMPL_SHIM(nsIApplicationCacheContainer)

#undef IMPL_SHIM

#define IID_IS(_i) aIID.Equals(NS_GET_IID(_i))

#define TRY_SHIM(_i)                                                       \
  PR_BEGIN_MACRO                                                           \
    if (IID_IS(_i)) {                                                      \
      nsCOMPtr<_i> real = do_GetInterface(mCallbacks);                     \
      if (!real) {                                                         \
        return NS_NOINTERFACE;                                             \
      }                                                                    \
      nsCOMPtr<_i> shim = new _i##Shim(this, real);                        \
      if (!shim) {                                                         \
        return NS_ERROR_OUT_OF_MEMORY;                                     \
      }                                                                    \
      *aSink = shim.forget().get();                                        \
      return NS_OK;                                                        \
    }                                                                      \
  PR_END_MACRO

NS_IMETHODIMP
nsExternalResourceMap::LoadgroupCallbacks::GetInterface(const nsIID & aIID,
                                                        void **aSink)
{
  if (mCallbacks &&
      (IID_IS(nsIPrompt) || IID_IS(nsIAuthPrompt) || IID_IS(nsIAuthPrompt2) ||
       IID_IS(nsITabChild))) {
    return mCallbacks->GetInterface(aIID, aSink);
  }

  *aSink = nullptr;

  TRY_SHIM(nsILoadContext);
  TRY_SHIM(nsIProgressEventSink);
  TRY_SHIM(nsIChannelEventSink);
  TRY_SHIM(nsISecurityEventSink);
  TRY_SHIM(nsIApplicationCacheContainer);

  return NS_NOINTERFACE;
}

#undef TRY_SHIM
#undef IID_IS

nsExternalResourceMap::ExternalResource::~ExternalResource()
{
  if (mViewer) {
    mViewer->Close(nullptr);
    mViewer->Destroy();
  }
}

// ==================================================================
// =
// ==================================================================

// If we ever have an nsIDocumentObserver notification for stylesheet title
// changes, we could make this inherit from nsDOMStringList instead of
// reimplementing nsIDOMDOMStringList.
class nsDOMStyleSheetSetList MOZ_FINAL : public nsIDOMDOMStringList
{
public:
  NS_DECL_ISUPPORTS

  NS_DECL_NSIDOMDOMSTRINGLIST

  nsDOMStyleSheetSetList(nsIDocument* aDocument);

  void Disconnect()
  {
    mDocument = nullptr;
  }

protected:
  // Rebuild our list of style sets
  nsresult GetSets(nsTArray<nsString>& aStyleSets);

  nsIDocument* mDocument;  // Our document; weak ref.  It'll let us know if it
                           // dies.
};

NS_IMPL_ADDREF(nsDOMStyleSheetSetList)
NS_IMPL_RELEASE(nsDOMStyleSheetSetList)
NS_INTERFACE_TABLE_HEAD(nsDOMStyleSheetSetList)
  NS_INTERFACE_TABLE1(nsDOMStyleSheetSetList, nsIDOMDOMStringList)
  NS_INTERFACE_TABLE_TO_MAP_SEGUE
  NS_DOM_INTERFACE_MAP_ENTRY_CLASSINFO(DOMStringList)
NS_INTERFACE_MAP_END

nsDOMStyleSheetSetList::nsDOMStyleSheetSetList(nsIDocument* aDocument)
  : mDocument(aDocument)
{
  NS_ASSERTION(mDocument, "Must have document!");
}

NS_IMETHODIMP
nsDOMStyleSheetSetList::Item(uint32_t aIndex, nsAString& aResult)
{
  nsTArray<nsString> styleSets;
  nsresult rv = GetSets(styleSets);
  NS_ENSURE_SUCCESS(rv, rv);

  if (aIndex >= styleSets.Length()) {
    SetDOMStringToNull(aResult);
  } else {
    aResult = styleSets[aIndex];
  }

  return NS_OK;
}

NS_IMETHODIMP
nsDOMStyleSheetSetList::GetLength(uint32_t *aLength)
{
  nsTArray<nsString> styleSets;
  nsresult rv = GetSets(styleSets);
  NS_ENSURE_SUCCESS(rv, rv);

  *aLength = styleSets.Length();

  return NS_OK;
}

NS_IMETHODIMP
nsDOMStyleSheetSetList::Contains(const nsAString& aString, bool *aResult)
{
  nsTArray<nsString> styleSets;
  nsresult rv = GetSets(styleSets);
  NS_ENSURE_SUCCESS(rv, rv);

  *aResult = styleSets.Contains(aString);

  return NS_OK;
}

nsresult
nsDOMStyleSheetSetList::GetSets(nsTArray<nsString>& aStyleSets)
{
  if (!mDocument) {
    return NS_OK; // Spec says "no exceptions", and we have no style sets if we
                  // have no document, for sure
  }

  int32_t count = mDocument->GetNumberOfStyleSheets();
  nsAutoString title;
  for (int32_t index = 0; index < count; index++) {
    nsIStyleSheet* sheet = mDocument->GetStyleSheetAt(index);
    NS_ASSERTION(sheet, "Null sheet in sheet list!");
    sheet->GetTitle(title);
    if (!title.IsEmpty() && !aStyleSets.Contains(title) &&
        !aStyleSets.AppendElement(title)) {
      return NS_ERROR_OUT_OF_MEMORY;
    }
  }

  return NS_OK;
}

// ==================================================================

struct nsIDocument::FrameRequest
{
  FrameRequest(const FrameRequestCallbackHolder& aCallback,
               int32_t aHandle) :
    mCallback(aCallback),
    mHandle(aHandle)
  {}

  // Conversion operator so that we can append these to a
  // FrameRequestCallbackList
  operator const FrameRequestCallbackHolder& () const {
    return mCallback;
  }

  // Comparator operators to allow RemoveElementSorted with an
  // integer argument on arrays of FrameRequest
  bool operator==(int32_t aHandle) const {
    return mHandle == aHandle;
  }
  bool operator<(int32_t aHandle) const {
    return mHandle < aHandle;
  }

  FrameRequestCallbackHolder mCallback;
  int32_t mHandle;
};

// ==================================================================
// =
// ==================================================================
nsIDocument::nsIDocument()
  : nsINode(nullptr),
    mCharacterSet(NS_LITERAL_CSTRING("ISO-8859-1")),
    mNodeInfoManager(nullptr),
    mCompatMode(eCompatibility_FullStandards),
    mVisibilityState(dom::VisibilityState::Hidden),
    mIsInitialDocumentInWindow(false),
    mMayStartLayout(true),
    mVisible(true),
    mRemovedFromDocShell(false),
    // mAllowDNSPrefetch starts true, so that we can always reliably && it
    // with various values that might disable it.  Since we never prefetch
    // unless we get a window, and in that case the docshell value will get
    // &&-ed in, this is safe.
    mAllowDNSPrefetch(true),
    mIsBeingUsedAsImage(false),
    mHasLinksToUpdate(false),
    mPartID(0)
{
  SetInDocument();
}

// NOTE! nsDocument::operator new() zeroes out all members, so don't
// bother initializing members to 0.

nsDocument::nsDocument(const char* aContentType)
  : nsIDocument()
  , mAnimatingImages(true)
  , mViewportType(Unknown)
{
  SetContentTypeInternal(nsDependentCString(aContentType));

#ifdef PR_LOGGING
  if (!gDocumentLeakPRLog)
    gDocumentLeakPRLog = PR_NewLogModule("DocumentLeak");

  if (gDocumentLeakPRLog)
    PR_LOG(gDocumentLeakPRLog, PR_LOG_DEBUG,
           ("DOCUMENT %p created", this));

  if (!gCspPRLog)
    gCspPRLog = PR_NewLogModule("CSP");
#endif

  // Start out mLastStyleSheetSet as null, per spec
  SetDOMStringToNull(mLastStyleSheetSet);

  mLinksToUpdate.Init();
}

static PLDHashOperator
ClearAllBoxObjects(nsIContent* aKey, nsPIBoxObject* aBoxObject, void* aUserArg)
{
  if (aBoxObject) {
    aBoxObject->Clear();
  }
  return PL_DHASH_NEXT;
}

nsIDocument::~nsIDocument()
{
  if (mNodeInfoManager) {
    mNodeInfoManager->DropDocumentReference();
  }
}


nsDocument::~nsDocument()
{
#ifdef PR_LOGGING
  if (gDocumentLeakPRLog)
    PR_LOG(gDocumentLeakPRLog, PR_LOG_DEBUG,
           ("DOCUMENT %p destroyed", this));
#endif

  NS_ASSERTION(!mIsShowing, "Destroying a currently-showing document");

  if (IsTopLevelContentDocument()) {
    //don't report for about: pages
    nsCOMPtr<nsIPrincipal> principal = GetPrincipal();
    nsCOMPtr<nsIURI> uri;
    principal->GetURI(getter_AddRefs(uri));
    bool isAboutScheme = true;
    if (uri) {
      uri->SchemeIs("about", &isAboutScheme);
    }

    if (!isAboutScheme) {
      // Record the mixed content status of the docshell in Telemetry
      enum {
        NO_MIXED_CONTENT = 0, // There is no Mixed Content on the page
        MIXED_DISPLAY_CONTENT = 1, // The page attempted to load Mixed Display Content
        MIXED_ACTIVE_CONTENT = 2, // The page attempted to load Mixed Active Content
        MIXED_DISPLAY_AND_ACTIVE_CONTENT = 3 // The page attempted to load Mixed Display & Mixed Active Content
      };

      bool mixedActiveLoaded = GetHasMixedActiveContentLoaded();
      bool mixedActiveBlocked = GetHasMixedActiveContentBlocked();

      bool mixedDisplayLoaded = GetHasMixedDisplayContentLoaded();
      bool mixedDisplayBlocked = GetHasMixedDisplayContentBlocked();

      bool hasMixedDisplay = (mixedDisplayBlocked || mixedDisplayLoaded);
      bool hasMixedActive = (mixedActiveBlocked || mixedActiveLoaded);

      uint32_t mixedContentLevel = NO_MIXED_CONTENT;
      if (hasMixedDisplay && hasMixedActive) {
        mixedContentLevel = MIXED_DISPLAY_AND_ACTIVE_CONTENT;
      } else if (hasMixedActive){
        mixedContentLevel = MIXED_ACTIVE_CONTENT;
      } else if (hasMixedDisplay) {
        mixedContentLevel = MIXED_DISPLAY_CONTENT;
      }
      Accumulate(Telemetry::MIXED_CONTENT_PAGE_LOAD, mixedContentLevel);
    }
  }

  mInDestructor = true;
  mInUnlinkOrDeletion = true;

  mCustomPrototypes.Clear();

  nsISupports* supports;
  QueryInterface(NS_GET_IID(nsCycleCollectionISupports), reinterpret_cast<void**>(&supports));
  NS_ASSERTION(supports, "Failed to QI to nsCycleCollectionISupports?!");
  nsContentUtils::DropJSObjects(supports);

  // Clear mObservers to keep it in sync with the mutationobserver list
  mObservers.Clear();

  if (mStyleSheetSetList) {
    mStyleSheetSetList->Disconnect();
  }

  if (mAnimationController) {
    mAnimationController->Disconnect();
  }

  mParentDocument = nullptr;

  // Kill the subdocument map, doing this will release its strong
  // references, if any.
  if (mSubDocuments) {
    PL_DHashTableDestroy(mSubDocuments);

    mSubDocuments = nullptr;
  }

  // Destroy link map now so we don't waste time removing
  // links one by one
  DestroyElementMaps();

  nsAutoScriptBlocker scriptBlocker;

  int32_t indx; // must be signed
  uint32_t count = mChildren.ChildCount();
  for (indx = int32_t(count) - 1; indx >= 0; --indx) {
    mChildren.ChildAt(indx)->UnbindFromTree();
    mChildren.RemoveChildAt(indx);
  }
  mFirstChild = nullptr;
  mCachedRootElement = nullptr;

  // Let the stylesheets know we're going away
  indx = mStyleSheets.Count();
  while (--indx >= 0) {
    mStyleSheets[indx]->SetOwningDocument(nullptr);
  }
  indx = mCatalogSheets.Count();
  while (--indx >= 0) {
    static_cast<nsCSSStyleSheet*>(mCatalogSheets[indx])->SetOwningNode(nullptr);
    mCatalogSheets[indx]->SetOwningDocument(nullptr);
  }
  if (mAttrStyleSheet) {
    mAttrStyleSheet->SetOwningDocument(nullptr);
  }

  if (mListenerManager) {
    mListenerManager->Disconnect();
    UnsetFlags(NODE_HAS_LISTENERMANAGER);
  }

  if (mScriptLoader) {
    mScriptLoader->DropDocumentReference();
  }

  if (mCSSLoader) {
    // Could be null here if Init() failed
    mCSSLoader->DropDocumentReference();
  }

  if (mStyleImageLoader) {
    mStyleImageLoader->DropDocumentReference();
  }

  delete mHeaderData;

  if (mBoxObjectTable) {
    mBoxObjectTable->EnumerateRead(ClearAllBoxObjects, nullptr);
    delete mBoxObjectTable;
  }

  mPendingTitleChangeEvent.Revoke();

  for (uint32_t i = 0; i < mHostObjectURIs.Length(); ++i) {
    nsHostObjectProtocolHandler::RemoveDataEntry(mHostObjectURIs[i]);
  }

  // We don't want to leave residual locks on images. Make sure we're in an
  // unlocked state, and then clear the table.
  SetImageLockingState(false);
  mImageTracker.Clear();

  mPlugins.Clear();
}

NS_INTERFACE_TABLE_HEAD(nsDocument)
  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
  NS_INTERFACE_TABLE_BEGIN
    NS_INTERFACE_TABLE_ENTRY_AMBIGUOUS(nsDocument, nsISupports, nsINode)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsINode)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIDocument)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIDOMDocument)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIDOMNode)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIDOMDocumentXBL)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIScriptObjectPrincipal)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIDOMEventTarget)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, mozilla::dom::EventTarget)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsISupportsWeakReference)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIRadioGroupContainer)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIMutationObserver)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIApplicationCacheContainer)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIInlineEventHandlers)
    NS_INTERFACE_TABLE_ENTRY(nsDocument, nsIObserver)
  NS_INTERFACE_TABLE_END
  NS_INTERFACE_TABLE_TO_MAP_SEGUE_CYCLE_COLLECTION(nsDocument)
  NS_INTERFACE_MAP_ENTRY_TEAROFF(nsIDOMXPathNSResolver,
                                 new nsNode3Tearoff(this))
  if (aIID.Equals(NS_GET_IID(nsIDOMXPathEvaluator)) ||
      aIID.Equals(NS_GET_IID(nsIXPathEvaluatorInternal))) {
    if (!mXPathEvaluatorTearoff) {
      nsresult rv;
      mXPathEvaluatorTearoff =
        do_CreateInstance(NS_XPATH_EVALUATOR_CONTRACTID,
                          static_cast<nsIDocument *>(this), &rv);
      NS_ENSURE_SUCCESS(rv, rv);
    }

    return mXPathEvaluatorTearoff->QueryInterface(aIID, aInstancePtr);
  }
  else
NS_INTERFACE_MAP_END


NS_IMPL_CYCLE_COLLECTING_ADDREF(nsDocument)
NS_IMETHODIMP_(nsrefcnt)
nsDocument::Release()
{
  NS_PRECONDITION(0 != mRefCnt, "dup release");
  NS_ASSERT_OWNINGTHREAD_AND_NOT_CCTHREAD(nsDocument);
  nsISupports* base = NS_CYCLE_COLLECTION_CLASSNAME(nsDocument)::Upcast(this);
  nsrefcnt count = mRefCnt.decr(base);
  NS_LOG_RELEASE(this, count, "nsDocument");
  if (count == 0) {
    if (mStackRefCnt && !mNeedsReleaseAfterStackRefCntRelease) {
      mNeedsReleaseAfterStackRefCntRelease = true;
      NS_ADDREF_THIS();
      return mRefCnt.get();
    }
    NS_ASSERT_OWNINGTHREAD(nsDocument);
    nsNodeUtils::LastRelease(this);
  }
  return count;
}

NS_IMETHODIMP_(void)
nsDocument::DeleteCycleCollectable()
{
  delete this;
}

NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_BEGIN(nsDocument)
  if (Element::CanSkip(tmp, aRemovingAllowed)) {
    nsEventListenerManager* elm = tmp->GetListenerManager(false);
    if (elm) {
      elm->MarkForCC();
    }
    return true;
  }
NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_END

NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_IN_CC_BEGIN(nsDocument)
  return Element::CanSkipInCC(tmp);
NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_IN_CC_END

NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_THIS_BEGIN(nsDocument)
  return Element::CanSkipThis(tmp);
NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_THIS_END

static PLDHashOperator
SubDocTraverser(PLDHashTable *table, PLDHashEntryHdr *hdr, uint32_t number,
                void *arg)
{
  SubDocMapEntry *entry = static_cast<SubDocMapEntry*>(hdr);
  nsCycleCollectionTraversalCallback *cb =
    static_cast<nsCycleCollectionTraversalCallback*>(arg);

  NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*cb, "mSubDocuments entry->mKey");
  cb->NoteXPCOMChild(entry->mKey);
  NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*cb, "mSubDocuments entry->mSubDocument");
  cb->NoteXPCOMChild(entry->mSubDocument);

  return PL_DHASH_NEXT;
}

static PLDHashOperator
RadioGroupsTraverser(const nsAString& aKey, nsRadioGroupStruct* aData,
                     void* aClosure)
{
  nsCycleCollectionTraversalCallback *cb =
    static_cast<nsCycleCollectionTraversalCallback*>(aClosure);

  NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*cb,
                                   "mRadioGroups entry->mSelectedRadioButton");
  cb->NoteXPCOMChild(aData->mSelectedRadioButton);

  uint32_t i, count = aData->mRadioButtons.Count();
  for (i = 0; i < count; ++i) {
    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*cb,
                                       "mRadioGroups entry->mRadioButtons[i]");
    cb->NoteXPCOMChild(aData->mRadioButtons[i]);
  }

  return PL_DHASH_NEXT;
}

static PLDHashOperator
BoxObjectTraverser(nsIContent* key, nsPIBoxObject* boxObject, void* userArg)
{
  nsCycleCollectionTraversalCallback *cb =
    static_cast<nsCycleCollectionTraversalCallback*>(userArg);

  NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*cb, "mBoxObjectTable entry");
  cb->NoteXPCOMChild(boxObject);

  return PL_DHASH_NEXT;
}

static PLDHashOperator
IdentifierMapEntryTraverse(nsIdentifierMapEntry *aEntry, void *aArg)
{
  nsCycleCollectionTraversalCallback *cb =
    static_cast<nsCycleCollectionTraversalCallback*>(aArg);
  aEntry->Traverse(cb);
  return PL_DHASH_NEXT;
}

static const char* kNSURIs[] = {
  "([none])",
  "(xmlns)",
  "(xml)",
  "(xhtml)",
  "(XLink)",
  "(XSLT)",
  "(XBL)",
  "(MathML)",
  "(RDF)",
  "(XUL)"
};

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(nsDocument)
  if (MOZ_UNLIKELY(cb.WantDebugInfo())) {
    char name[512];
    nsAutoCString loadedAsData;
    if (tmp->IsLoadedAsData()) {
      loadedAsData.AssignLiteral("data");
    } else {
      loadedAsData.AssignLiteral("normal");
    }
    uint32_t nsid = tmp->GetDefaultNamespaceID();
    nsAutoCString uri;
    if (tmp->mDocumentURI)
      tmp->mDocumentURI->GetSpec(uri);
    if (nsid < ArrayLength(kNSURIs)) {
      PR_snprintf(name, sizeof(name), "nsDocument %s %s %s",
                  loadedAsData.get(), kNSURIs[nsid], uri.get());
    }
    else {
      PR_snprintf(name, sizeof(name), "nsDocument %s %s",
                  loadedAsData.get(), uri.get());
    }
    cb.DescribeRefCountedNode(tmp->mRefCnt.get(), name);
  }
  else {
    NS_IMPL_CYCLE_COLLECTION_DESCRIBE(nsDocument, tmp->mRefCnt.get())
  }

  // Always need to traverse script objects, so do that before we check
  // if we're uncollectable.
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS

  if (!nsINode::Traverse(tmp, cb)) {
    return NS_SUCCESS_INTERRUPTED_TRAVERSE;
  }

  tmp->mIdentifierMap.EnumerateEntries(IdentifierMapEntryTraverse, &cb);

  tmp->mExternalResourceMap.Traverse(&cb);

  // Traverse the mChildren nsAttrAndChildArray.
  for (int32_t indx = int32_t(tmp->mChildren.ChildCount()); indx > 0; --indx) {
    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mChildren[i]");
    cb.NoteXPCOMChild(tmp->mChildren.ChildAt(indx - 1));
  }

  // Traverse all nsIDocument pointer members.
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mSecurityInfo)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDisplayDocument)

  // Traverse all nsDocument nsCOMPtrs.
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParser)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mScriptGlobalObject)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mListenerManager)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDOMStyleSheets)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mScriptLoader)

  tmp->mRadioGroups.EnumerateRead(RadioGroupsTraverser, &cb);

  // The boxobject for an element will only exist as long as it's in the
  // document, so we'll traverse the table here instead of from the element.
  if (tmp->mBoxObjectTable) {
    tmp->mBoxObjectTable->EnumerateRead(BoxObjectTraverser, &cb);
  }

  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mChannel)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mStyleAttrStyleSheet)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mXPathEvaluatorTearoff)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mLayoutHistoryState)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mOnloadBlocker)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mFirstBaseNodeWithHref)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDOMImplementation)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mImageMaps)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mOriginalDocument)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mCachedEncoder)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mStateObjectCached)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mUndoManager)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mTemplateContentsOwner)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mChildrenCollection)

  // Traverse all our nsCOMArrays.
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mStyleSheets)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mCatalogSheets)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPreloadingImages)

  for (uint32_t i = 0; i < tmp->mFrameRequestCallbacks.Length(); ++i) {
    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mFrameRequestCallbacks[i]");
    cb.NoteXPCOMChild(tmp->mFrameRequestCallbacks[i].mCallback.GetISupports());
  }

  // Traverse animation components
  if (tmp->mAnimationController) {
    tmp->mAnimationController->Traverse(&cb);
  }

  if (tmp->mSubDocuments && tmp->mSubDocuments->ops) {
    PL_DHashTableEnumerate(tmp->mSubDocuments, SubDocTraverser, &cb);
  }

  if (tmp->mCSSLoader) {
    tmp->mCSSLoader->TraverseCachedSheets(cb);
  }

  for (uint32_t i = 0; i < tmp->mHostObjectURIs.Length(); ++i) {
    nsHostObjectProtocolHandler::Traverse(tmp->mHostObjectURIs[i], cb);
  }
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END


struct CustomPrototypeTraceArgs {
  const TraceCallbacks& callbacks;
  void* closure;
};


static PLDHashOperator
CustomPrototypeTrace(const nsAString& aName, JS::Heap<JSObject*>& aObject, void *aArg)
{
  CustomPrototypeTraceArgs* traceArgs = static_cast<CustomPrototypeTraceArgs*>(aArg);
  MOZ_ASSERT(aObject, "Protocol object value must not be null");
  traceArgs->callbacks.Trace(&aObject, "mCustomPrototypes entry", traceArgs->closure);
  return PL_DHASH_NEXT;
}


NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(nsDocument)
  CustomPrototypeTraceArgs customPrototypeArgs = { aCallbacks, aClosure };
  tmp->mCustomPrototypes.Enumerate(CustomPrototypeTrace, &customPrototypeArgs);
  if (tmp->PreservingWrapper()) {
    NS_IMPL_CYCLE_COLLECTION_TRACE_JSVAL_MEMBER_CALLBACK(mExpandoAndGeneration.expando);
  }
  NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
NS_IMPL_CYCLE_COLLECTION_TRACE_END


NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsDocument)
  tmp->mInUnlinkOrDeletion = true;

  // Clear out our external resources
  tmp->mExternalResourceMap.Shutdown();

  nsAutoScriptBlocker scriptBlocker;

  nsINode::Unlink(tmp);

  // Unlink the mChildren nsAttrAndChildArray.
  for (int32_t indx = int32_t(tmp->mChildren.ChildCount()) - 1;
       indx >= 0; --indx) {
    tmp->mChildren.ChildAt(indx)->UnbindFromTree();
    tmp->mChildren.RemoveChildAt(indx);
  }
  tmp->mFirstChild = nullptr;

  NS_IMPL_CYCLE_COLLECTION_UNLINK(mXPathEvaluatorTearoff)
  tmp->mCachedRootElement = nullptr; // Avoid a dangling pointer
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mDisplayDocument)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mFirstBaseNodeWithHref)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mDOMImplementation)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mImageMaps)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mOriginalDocument)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mCachedEncoder)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mUndoManager)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mTemplateContentsOwner)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mChildrenCollection)

  tmp->mParentDocument = nullptr;

  NS_IMPL_CYCLE_COLLECTION_UNLINK(mPreloadingImages)


  if (tmp->mBoxObjectTable) {
   tmp->mBoxObjectTable->EnumerateRead(ClearAllBoxObjects, nullptr);
   delete tmp->mBoxObjectTable;
   tmp->mBoxObjectTable = nullptr;
 }

  if (tmp->mListenerManager) {
    tmp->mListenerManager->Disconnect();
    tmp->UnsetFlags(NODE_HAS_LISTENERMANAGER);
    tmp->mListenerManager = nullptr;
  }

  if (tmp->mSubDocuments) {
    PL_DHashTableDestroy(tmp->mSubDocuments);
    tmp->mSubDocuments = nullptr;
  }

  tmp->mFrameRequestCallbacks.Clear();

  tmp->mRadioGroups.Clear();

  // nsDocument has a pretty complex destructor, so we're going to
  // assume that *most* cycles you actually want to break somewhere
  // else, and not unlink an awful lot here.

  tmp->mIdentifierMap.Clear();
  tmp->mExpandoAndGeneration.Unlink();

  tmp->mCustomPrototypes.Clear();

  if (tmp->mAnimationController) {
    tmp->mAnimationController->Unlink();
  }

  tmp->mPendingTitleChangeEvent.Revoke();

  if (tmp->mCSSLoader) {
    tmp->mCSSLoader->UnlinkCachedSheets();
  }

  for (uint32_t i = 0; i < tmp->mHostObjectURIs.Length(); ++i) {
    nsHostObjectProtocolHandler::RemoveDataEntry(tmp->mHostObjectURIs[i]);
  }

  tmp->mInUnlinkOrDeletion = false;
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

static bool sPrefsInitialized = false;
static uint32_t sOnloadDecodeLimit = 0;

nsresult
nsDocument::Init()
{
  if (mCSSLoader || mStyleImageLoader || mNodeInfoManager || mScriptLoader) {
    return NS_ERROR_ALREADY_INITIALIZED;
  }

  if (!sPrefsInitialized) {
    sPrefsInitialized = true;
    Preferences::AddUintVarCache(&sOnloadDecodeLimit, "image.onload.decode.limit", 0);
  }

  mIdentifierMap.Init();
  mStyledLinks.Init();
  mRadioGroups.Init();
  mCustomPrototypes.Init();

  // If after creation the owner js global is not set for a document
  // we use the default compartment for this document, instead of creating
  // wrapper in some random compartment when the document is exposed to js
  // via some events.
  nsCOMPtr<nsIGlobalObject> global = xpc::GetJunkScopeGlobal();
  NS_ENSURE_TRUE(global, NS_ERROR_FAILURE);
  mScopeObject = do_GetWeakReference(global);
  MOZ_ASSERT(mScopeObject);

  // Force initialization.
  nsINode::nsSlots* slots = Slots();

  // Prepend self as mutation-observer whether we need it or not (some
  // subclasses currently do, other don't). This is because the code in
  // nsNodeUtils always notifies the first observer first, expecting the
  // first observer to be the document.
  NS_ENSURE_TRUE(slots->mMutationObservers.PrependElementUnlessExists(static_cast<nsIMutationObserver*>(this)),
                 NS_ERROR_OUT_OF_MEMORY);


  mOnloadBlocker = new nsOnloadBlocker();
  mCSSLoader = new mozilla::css::Loader(this);
  // Assume we're not quirky, until we know otherwise
  mCSSLoader->SetCompatibilityMode(eCompatibility_FullStandards);

  mStyleImageLoader = new mozilla::css::ImageLoader(this);

  mNodeInfoManager = new nsNodeInfoManager();
  nsresult rv = mNodeInfoManager->Init(this);
  NS_ENSURE_SUCCESS(rv, rv);

  // mNodeInfo keeps NodeInfoManager alive!
  mNodeInfo = mNodeInfoManager->GetDocumentNodeInfo();
  NS_ENSURE_TRUE(mNodeInfo, NS_ERROR_OUT_OF_MEMORY);
  NS_ABORT_IF_FALSE(mNodeInfo->NodeType() == nsIDOMNode::DOCUMENT_NODE,
                    "Bad NodeType in aNodeInfo");

  NS_ASSERTION(OwnerDoc() == this, "Our nodeinfo is busted!");

  mScriptLoader = new nsScriptLoader(this);

  mImageTracker.Init();
  mPlugins.Init();

  nsXPCOMCycleCollectionParticipant* participant;
  CallQueryInterface(this, &participant);
  NS_ASSERTION(participant, "Failed to QI to nsXPCOMCycleCollectionParticipant!");

  nsISupports* thisSupports;
  QueryInterface(NS_GET_IID(nsCycleCollectionISupports), reinterpret_cast<void**>(&thisSupports));
  NS_ASSERTION(thisSupports, "Failed to QI to nsCycleCollectionISupports!");
  nsContentUtils::HoldJSObjects(thisSupports, participant);

  return NS_OK;
}

void
nsIDocument::DeleteAllProperties()
{
  for (uint32_t i = 0; i < GetPropertyTableCount(); ++i) {
    PropertyTable(i)->DeleteAllProperties();
  }
}

void
nsIDocument::DeleteAllPropertiesFor(nsINode* aNode)
{
  for (uint32_t i = 0; i < GetPropertyTableCount(); ++i) {
    PropertyTable(i)->DeleteAllPropertiesFor(aNode);
  }
}

nsPropertyTable*
nsIDocument::GetExtraPropertyTable(uint16_t aCategory)
{
  NS_ASSERTION(aCategory > 0, "Category 0 should have already been handled");
  while (aCategory >= mExtraPropertyTables.Length() + 1) {
    mExtraPropertyTables.AppendElement(new nsPropertyTable());
  }
  return mExtraPropertyTables[aCategory - 1];
}

bool
nsIDocument::IsVisibleConsideringAncestors() const
{
  const nsIDocument *parent = this;
  do {
    if (!parent->IsVisible()) {
      return false;
    }
  } while ((parent = parent->GetParentDocument()));

  return true;
      }

void
nsDocument::Reset(nsIChannel* aChannel, nsILoadGroup* aLoadGroup)
{
  nsCOMPtr<nsIURI> uri;
  nsCOMPtr<nsIPrincipal> principal;
  if (aChannel) {
    // Note: this code is duplicated in XULDocument::StartDocumentLoad and
    // nsScriptSecurityManager::GetChannelPrincipal.
    // Note: this should match nsDocShell::OnLoadingSite
    NS_GetFinalChannelURI(aChannel, getter_AddRefs(uri));

    nsIScriptSecurityManager *securityManager =
      nsContentUtils::GetSecurityManager();
    if (securityManager) {
      securityManager->GetChannelPrincipal(aChannel,
                                           getter_AddRefs(principal));
    }
  }

  ResetToURI(uri, aLoadGroup, principal);

  nsCOMPtr<nsIPropertyBag2> bag = do_QueryInterface(aChannel);
  if (bag) {
    nsCOMPtr<nsIURI> baseURI;
    bag->GetPropertyAsInterface(NS_LITERAL_STRING("baseURI"),
                                NS_GET_IID(nsIURI), getter_AddRefs(baseURI));
    if (baseURI) {
      mDocumentBaseURI = baseURI;
    }
  }

  mChannel = aChannel;
}

void
nsDocument::ResetToURI(nsIURI *aURI, nsILoadGroup *aLoadGroup,
                       nsIPrincipal* aPrincipal)
{
  NS_PRECONDITION(aURI, "Null URI passed to ResetToURI");

#ifdef PR_LOGGING
  if (gDocumentLeakPRLog && PR_LOG_TEST(gDocumentLeakPRLog, PR_LOG_DEBUG)) {
    nsAutoCString spec;
    aURI->GetSpec(spec);
    PR_LogPrint("DOCUMENT %p ResetToURI %s", this, spec.get());
  }
#endif

  mSecurityInfo = nullptr;

  mDocumentLoadGroup = nullptr;

  // Delete references to sub-documents and kill the subdocument map,
  // if any. It holds strong references
  if (mSubDocuments) {
    PL_DHashTableDestroy(mSubDocuments);

    mSubDocuments = nullptr;
  }

  // Destroy link map now so we don't waste time removing
  // links one by one
  DestroyElementMaps();

  bool oldVal = mInUnlinkOrDeletion;
  mInUnlinkOrDeletion = true;
  uint32_t count = mChildren.ChildCount();
  { // Scope for update
    MOZ_AUTO_DOC_UPDATE(this, UPDATE_CONTENT_MODEL, true);
    for (int32_t i = int32_t(count) - 1; i >= 0; i--) {
      nsCOMPtr<nsIContent> content = mChildren.ChildAt(i);

      nsIContent* previousSibling = content->GetPreviousSibling();

      if (nsINode::GetFirstChild() == content) {
        mFirstChild = content->GetNextSibling();
      }
      mChildren.RemoveChildAt(i);
      nsNodeUtils::ContentRemoved(this, content, i, previousSibling);
      content->UnbindFromTree();
    }
    mCachedRootElement = nullptr;
  }
  mInUnlinkOrDeletion = oldVal;

  mCustomPrototypes.Clear();

  // Reset our stylesheets
  ResetStylesheetsToURI(aURI);

  // Release the listener manager
  if (mListenerManager) {
    mListenerManager->Disconnect();
    mListenerManager = nullptr;
  }

  // Release the stylesheets list.
  mDOMStyleSheets = nullptr;

  // Release our principal after tearing down the document, rather than before.
  // This ensures that, during teardown, the document and the dying window (which
  // already nulled out its document pointer and cached the principal) have
  // matching principals.
  SetPrincipal(nullptr);

  // Clear the original URI so SetDocumentURI sets it.
  mOriginalURI = nullptr;

  SetDocumentURI(aURI);
  // If mDocumentBaseURI is null, nsIDocument::GetBaseURI() returns
  // mDocumentURI.
  mDocumentBaseURI = nullptr;

  if (aLoadGroup) {
    mDocumentLoadGroup = do_GetWeakReference(aLoadGroup);
    // there was an assertion here that aLoadGroup was not null.  This
    // is no longer valid: nsDocShell::SetDocument does not create a
    // load group, and it works just fine

    // XXXbz what does "just fine" mean exactly?  And given that there
    // is no nsDocShell::SetDocument, what is this talking about?
  }

  mLastModified.Truncate();
  // XXXbz I guess we're assuming that the caller will either pass in
  // a channel with a useful type or call SetContentType?
  SetContentTypeInternal(EmptyCString());
  mContentLanguage.Truncate();
  mBaseTarget.Truncate();
  mReferrer.Truncate();

  mXMLDeclarationBits = 0;

  // Now get our new principal
  if (aPrincipal) {
    SetPrincipal(aPrincipal);
  } else {
    nsIScriptSecurityManager *securityManager =
      nsContentUtils::GetSecurityManager();
    if (securityManager) {
      nsCOMPtr<nsIDocShell> docShell = do_QueryReferent(mDocumentContainer);

      if (!docShell && aLoadGroup) {
        nsCOMPtr<nsIInterfaceRequestor> cbs;
        aLoadGroup->GetNotificationCallbacks(getter_AddRefs(cbs));
        docShell = do_GetInterface(cbs);
      }

      MOZ_ASSERT(docShell,
                 "must be in a docshell or pass in an explicit principal");

      nsCOMPtr<nsIPrincipal> principal;
      nsresult rv = securityManager->
        GetDocShellCodebasePrincipal(mDocumentURI, docShell,
                                     getter_AddRefs(principal));
      if (NS_SUCCEEDED(rv)) {
        SetPrincipal(principal);
      }
    }
  }

  // Refresh the principal on the compartment.
  nsPIDOMWindow* win = GetInnerWindow();
  if (win) {
    win->RefreshCompartmentPrincipal();
  }
}

void
nsDocument::RemoveDocStyleSheetsFromStyleSets()
{
  // The stylesheets should forget us
  int32_t indx = mStyleSheets.Count();
  while (--indx >= 0) {
    nsIStyleSheet* sheet = mStyleSheets[indx];
    sheet->SetOwningDocument(nullptr);

    if (sheet->IsApplicable()) {
      nsCOMPtr<nsIPresShell> shell = GetShell();
      if (shell) {
        shell->StyleSet()->RemoveDocStyleSheet(sheet);
      }
    }
    // XXX Tell observers?
  }
}

void
nsDocument::RemoveStyleSheetsFromStyleSets(nsCOMArray<nsIStyleSheet>& aSheets, nsStyleSet::sheetType aType)
{
  // The stylesheets should forget us
  int32_t indx = aSheets.Count();
  while (--indx >= 0) {
    nsIStyleSheet* sheet = aSheets[indx];
    sheet->SetOwningDocument(nullptr);

    if (sheet->IsApplicable()) {
      nsCOMPtr<nsIPresShell> shell = GetShell();
      if (shell) {
        shell->StyleSet()->RemoveStyleSheet(aType, sheet);
      }
    }

    // XXX Tell observers?
  }

}

void
nsDocument::ResetStylesheetsToURI(nsIURI* aURI)
{
  MOZ_ASSERT(aURI);

  mozAutoDocUpdate upd(this, UPDATE_STYLE, true);
  RemoveDocStyleSheetsFromStyleSets();
  RemoveStyleSheetsFromStyleSets(mCatalogSheets, nsStyleSet::eAgentSheet);
  RemoveStyleSheetsFromStyleSets(mAdditionalSheets[eAgentSheet], nsStyleSet::eAgentSheet);
  RemoveStyleSheetsFromStyleSets(mAdditionalSheets[eUserSheet], nsStyleSet::eUserSheet);
  RemoveStyleSheetsFromStyleSets(mAdditionalSheets[eAuthorSheet], nsStyleSet::eDocSheet);

  // Release all the sheets
  mStyleSheets.Clear();
  for (uint32_t i = 0; i < SheetTypeCount; ++i)
    mAdditionalSheets[i].Clear();

  // NOTE:  We don't release the catalog sheets.  It doesn't really matter
  // now, but it could in the future -- in which case not releasing them
  // is probably the right thing to do.

  // Now reset our inline style and attribute sheets.
  if (mAttrStyleSheet) {
    mAttrStyleSheet->Reset();
    mAttrStyleSheet->SetOwningDocument(this);
  } else {
    mAttrStyleSheet = new nsHTMLStyleSheet(this);
  }

  if (!mStyleAttrStyleSheet) {
    mStyleAttrStyleSheet = new nsHTMLCSSStyleSheet();
  }

  // Now set up our style sets
  nsCOMPtr<nsIPresShell> shell = GetShell();
  if (shell) {
    FillStyleSet(shell->StyleSet());
  }
}

static bool
AppendAuthorSheet(nsIStyleSheet *aSheet, void *aData)
{
  nsStyleSet *styleSet = static_cast<nsStyleSet*>(aData);
  styleSet->AppendStyleSheet(nsStyleSet::eDocSheet, aSheet);
  return true;
}

static void
AppendSheetsToStyleSet(nsStyleSet* aStyleSet,
                       const nsCOMArray<nsIStyleSheet>& aSheets,
                       nsStyleSet::sheetType aType)
{
  for (int32_t i = aSheets.Count() - 1; i >= 0; --i) {
    aStyleSet->AppendStyleSheet(aType, aSheets[i]);
  }
}


void
nsDocument::FillStyleSet(nsStyleSet* aStyleSet)
{
  NS_PRECONDITION(aStyleSet, "Must have a style set");
  NS_PRECONDITION(aStyleSet->SheetCount(nsStyleSet::eDocSheet) == 0,
                  "Style set already has document sheets?");

  // We could consider moving this to nsStyleSet::Init, to match its
  // handling of the eAnimationSheet and eTransitionSheet levels.
  aStyleSet->DirtyRuleProcessors(nsStyleSet::ePresHintSheet);
  aStyleSet->DirtyRuleProcessors(nsStyleSet::eStyleAttrSheet);

  int32_t i;
  for (i = mStyleSheets.Count() - 1; i >= 0; --i) {
    nsIStyleSheet* sheet = mStyleSheets[i];
    if (sheet->IsApplicable()) {
      aStyleSet->AddDocStyleSheet(sheet, this);
    }
  }

  nsStyleSheetService *sheetService = nsStyleSheetService::GetInstance();
  if (sheetService) {
    sheetService->AuthorStyleSheets()->EnumerateForwards(AppendAuthorSheet,
                                                         aStyleSet);
  }

  for (i = mCatalogSheets.Count() - 1; i >= 0; --i) {
    nsIStyleSheet* sheet = mCatalogSheets[i];
    if (sheet->IsApplicable()) {
      aStyleSet->AppendStyleSheet(nsStyleSet::eAgentSheet, sheet);
    }
  }

  AppendSheetsToStyleSet(aStyleSet, mAdditionalSheets[eAgentSheet],
                         nsStyleSet::eAgentSheet);
  AppendSheetsToStyleSet(aStyleSet, mAdditionalSheets[eUserSheet],
                         nsStyleSet::eUserSheet);
  AppendSheetsToStyleSet(aStyleSet, mAdditionalSheets[eAuthorSheet],
                         nsStyleSet::eDocSheet);
}

nsresult
nsDocument::StartDocumentLoad(const char* aCommand, nsIChannel* aChannel,
                              nsILoadGroup* aLoadGroup,
                              nsISupports* aContainer,
                              nsIStreamListener **aDocListener,
                              bool aReset, nsIContentSink* aSink)
{
#ifdef PR_LOGGING
  if (gDocumentLeakPRLog && PR_LOG_TEST(gDocumentLeakPRLog, PR_LOG_DEBUG)) {
    nsCOMPtr<nsIURI> uri;
    aChannel->GetURI(getter_AddRefs(uri));
    nsAutoCString spec;
    if (uri)
      uri->GetSpec(spec);
    PR_LogPrint("DOCUMENT %p StartDocumentLoad %s", this, spec.get());
  }
#endif

#ifdef DEBUG
  {
    uint32_t appId;
    nsresult rv = NodePrincipal()->GetAppId(&appId);
    NS_ENSURE_SUCCESS(rv, rv);
    MOZ_ASSERT(appId != nsIScriptSecurityManager::UNKNOWN_APP_ID,
               "Document should never have UNKNOWN_APP_ID");
  }
#endif

  MOZ_ASSERT(GetReadyStateEnum() == nsIDocument::READYSTATE_UNINITIALIZED,
             "Bad readyState");
  SetReadyStateInternal(READYSTATE_LOADING);

  if (nsCRT::strcmp(kLoadAsData, aCommand) == 0) {
    mLoadedAsData = true;
    // We need to disable script & style loading in this case.
    // We leave them disabled even in EndLoad(), and let anyone
    // who puts the document on display to worry about enabling.

    // Do not load/process scripts when loading as data
    ScriptLoader()->SetEnabled(false);

    // styles
    CSSLoader()->SetEnabled(false); // Do not load/process styles when loading as data
  } else if (nsCRT::strcmp("external-resource", aCommand) == 0) {
    // Allow CSS, but not scripts
    ScriptLoader()->SetEnabled(false);
  }

  mMayStartLayout = false;

  mHaveInputEncoding = true;

  if (aReset) {
    Reset(aChannel, aLoadGroup);
  }

  nsAutoCString contentType;
  nsCOMPtr<nsIPropertyBag2> bag = do_QueryInterface(aChannel);
  if ((bag && NS_SUCCEEDED(bag->GetPropertyAsACString(
                NS_LITERAL_STRING("contentType"), contentType))) ||
      NS_SUCCEEDED(aChannel->GetContentType(contentType))) {
    // XXX this is only necessary for viewsource:
    nsACString::const_iterator start, end, semicolon;
    contentType.BeginReading(start);
    contentType.EndReading(end);
    semicolon = start;
    FindCharInReadable(';', semicolon, end);
    SetContentTypeInternal(Substring(start, semicolon));
  }

  RetrieveRelevantHeaders(aChannel);

  mChannel = aChannel;
  nsCOMPtr<nsIInputStreamChannel> inStrmChan = do_QueryInterface(mChannel);
  if (inStrmChan) {
    bool isSrcdocChannel;
    inStrmChan->GetIsSrcdocChannel(&isSrcdocChannel);
    if (isSrcdocChannel) {
      mIsSrcdocDocument = true;
    }
  }

  // If this document is being loaded by a docshell, copy its sandbox flags
  // to the document. These are immutable after being set here.
  nsCOMPtr<nsIDocShell> docShell = do_QueryInterface(aContainer);

  if (docShell) {
    nsresult rv = docShell->GetSandboxFlags(&mSandboxFlags);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  nsresult rv = InitCSP(aChannel);
  NS_ENSURE_SUCCESS(rv, rv);

  return NS_OK;
}

void
CSPErrorQueue::Add(const char* aMessageName)
{
  mErrors.AppendElement(aMessageName);
}

void
CSPErrorQueue::Flush(nsIDocument* aDocument)
{
  for (uint32_t i = 0; i < mErrors.Length(); i++) {
    nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,
        "CSP", aDocument,
        nsContentUtils::eSECURITY_PROPERTIES,
        mErrors[i]);
  }
  mErrors.Clear();
}

nsresult
nsDocument::InitCSP(nsIChannel* aChannel)
{
  nsCOMPtr<nsIContentSecurityPolicy> csp;
  if (!CSPService::sCSPEnabled) {
#ifdef PR_LOGGING
    PR_LOG(gCspPRLog, PR_LOG_DEBUG,
           ("CSP is disabled, skipping CSP init for document %p", this));
#endif
    return NS_OK;
  }

  nsAutoCString tCspHeaderValue, tCspROHeaderValue;
  nsAutoCString tCspOldHeaderValue, tCspOldROHeaderValue;

  nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(aChannel);
  if (httpChannel) {
    httpChannel->GetResponseHeader(
        NS_LITERAL_CSTRING("x-content-security-policy"),
        tCspOldHeaderValue);

    httpChannel->GetResponseHeader(
        NS_LITERAL_CSTRING("x-content-security-policy-report-only"),
        tCspOldROHeaderValue);

    httpChannel->GetResponseHeader(
        NS_LITERAL_CSTRING("content-security-policy"),
        tCspHeaderValue);

    httpChannel->GetResponseHeader(
        NS_LITERAL_CSTRING("content-security-policy-report-only"),
        tCspROHeaderValue);
  }
  NS_ConvertASCIItoUTF16 cspHeaderValue(tCspHeaderValue);
  NS_ConvertASCIItoUTF16 cspROHeaderValue(tCspROHeaderValue);
  NS_ConvertASCIItoUTF16 cspOldHeaderValue(tCspOldHeaderValue);
  NS_ConvertASCIItoUTF16 cspOldROHeaderValue(tCspOldROHeaderValue);

  // Only use the CSP 1.0 spec compliant headers if a pref to do so
  // is set. This lets us turn on the 1.0 parser per platform. This
  // pref is also set by the tests for 1.0 spec compliant CSP.
  bool specCompliantEnabled =
    Preferences::GetBool("security.csp.speccompliant");

  if ((!cspHeaderValue.IsEmpty() || !cspROHeaderValue.IsEmpty()) &&
       !specCompliantEnabled) {
    // If spec compliant pref isn't set, pretend we never got
    // these headers.
    if (!specCompliantEnabled) {
      PR_LOG(gCspPRLog, PR_LOG_DEBUG,
             ("Got spec compliant CSP headers but pref was not set"));
      cspHeaderValue.Truncate();
      cspROHeaderValue.Truncate();
    }
  }

  // Figure out if we need to apply an app default CSP or a CSP from an app manifest
  bool applyAppDefaultCSP = false;
  bool applyAppManifestCSP = false;

  nsIPrincipal* principal = NodePrincipal();

  bool unknownAppId;
  uint16_t appStatus = nsIPrincipal::APP_STATUS_NOT_INSTALLED;
  nsAutoString appManifestCSP;
  if (NS_SUCCEEDED(principal->GetUnknownAppId(&unknownAppId)) &&
      !unknownAppId &&
      NS_SUCCEEDED(principal->GetAppStatus(&appStatus))) {
    applyAppDefaultCSP = ( appStatus == nsIPrincipal::APP_STATUS_PRIVILEGED ||
                           appStatus == nsIPrincipal::APP_STATUS_CERTIFIED);

    if (appStatus != nsIPrincipal::APP_STATUS_NOT_INSTALLED) {
      nsCOMPtr<nsIAppsService> appsService = do_GetService(APPS_SERVICE_CONTRACTID);
      if (appsService) {
        uint32_t appId = 0;
        if (NS_SUCCEEDED(principal->GetAppId(&appId))) {
          appsService->GetCSPByLocalId(appId, appManifestCSP);
          if (!appManifestCSP.IsEmpty()) {
            applyAppManifestCSP = true;
          }
        }
      }
    }
  }
#ifdef PR_LOGGING
  else
    PR_LOG(gCspPRLog, PR_LOG_DEBUG, ("Failed to get app status from principal"));
#endif

  // If there's no CSP to apply, go ahead and return early
  if (!applyAppDefaultCSP &&
      !applyAppManifestCSP &&
      cspHeaderValue.IsEmpty() &&
      cspROHeaderValue.IsEmpty() &&
      cspOldHeaderValue.IsEmpty() &&
      cspOldROHeaderValue.IsEmpty()) {
#ifdef PR_LOGGING
    nsCOMPtr<nsIURI> chanURI;
    aChannel->GetURI(getter_AddRefs(chanURI));
    nsAutoCString aspec;
    chanURI->GetAsciiSpec(aspec);
    PR_LOG(gCspPRLog, PR_LOG_DEBUG,
           ("no CSP for document, %s, %s",
            aspec.get(),
            applyAppDefaultCSP ? "is app" : "not an app"));
#endif
    return NS_OK;
  }

#ifdef PR_LOGGING
  PR_LOG(gCspPRLog, PR_LOG_DEBUG, ("Document is an app or CSP header specified %p", this));
#endif

  nsresult rv;
  csp = do_CreateInstance("@mozilla.org/contentsecuritypolicy;1", &rv);

  if (NS_FAILED(rv)) {
#ifdef PR_LOGGING
    PR_LOG(gCspPRLog, PR_LOG_DEBUG, ("Failed to create CSP object: %x", rv));
#endif
    return rv;
  }

  // used as a "self" identifier for the CSP.
  nsCOMPtr<nsIURI> chanURI;
  aChannel->GetURI(getter_AddRefs(chanURI));

  // Store the request context for violation reports
  csp->ScanRequestData(httpChannel);

  // The CSP is refined in the following order:
  // 1. Default app CSP, if applicable
  // 2. App manifest CSP, if provided
  // 3. HTTP header CSP, if provided
  // Note that since each application of refinePolicy is a set intersection,
  // the order in which multiple CSP's are refined does not matter.

  if (applyAppDefaultCSP) {
    nsAdoptingString appCSP;
    if (appStatus ==  nsIPrincipal::APP_STATUS_PRIVILEGED) {
      appCSP = Preferences::GetString("security.apps.privileged.CSP.default");
      NS_ASSERTION(appCSP, "App, but no default CSP in security.apps.privileged.CSP.default");
    } else if (appStatus == nsIPrincipal::APP_STATUS_CERTIFIED) {
      appCSP = Preferences::GetString("security.apps.certified.CSP.default");
      NS_ASSERTION(appCSP, "App, but no default CSP in security.apps.certified.CSP.default");
    }

    if (appCSP)
      // Use the 1.0 CSP parser for apps if the pref to do so is set.
      csp->RefinePolicy(appCSP, chanURI, specCompliantEnabled);
  }

  if (applyAppManifestCSP) {
    // Use the 1.0 CSP parser for apps if the pref to do so is set.
    csp->RefinePolicy(appManifestCSP, chanURI, specCompliantEnabled);
  }

  // While we are supporting both CSP 1.0 and the x- headers, the 1.0 headers
  // take priority.  If any spec-compliant headers are present, the x- headers
  // are ignored, and the spec compliant parser is used.
  bool cspSpecCompliant = (!cspHeaderValue.IsEmpty() || !cspROHeaderValue.IsEmpty());

  // If the old header is present, warn that it will be deprecated.
  if (!cspOldHeaderValue.IsEmpty() || !cspOldROHeaderValue.IsEmpty()) {
    mCSPWebConsoleErrorQueue.Add("OldCSPHeaderDeprecated");

    // Also, if the new headers AND the old headers were present, warn
    // that the old headers will be ignored.
    if (cspSpecCompliant) {
      mCSPWebConsoleErrorQueue.Add("BothCSPHeadersPresent");
    }
  }

  // ----- if there's a full-strength CSP header, apply it.
  bool applyCSPFromHeader =
    (( cspSpecCompliant && !cspHeaderValue.IsEmpty()) ||
     (!cspSpecCompliant && !cspOldHeaderValue.IsEmpty()));

  if (applyCSPFromHeader) {
    // Need to tokenize the header value since multiple headers could be
    // concatenated into one comma-separated list of policies.
    // See RFC2616 section 4.2 (last paragraph)
    nsCharSeparatedTokenizer tokenizer(cspSpecCompliant ?
                                       cspHeaderValue :
                                       cspOldHeaderValue, ',');
    while (tokenizer.hasMoreTokens()) {
        const nsSubstring& policy = tokenizer.nextToken();
        csp->RefinePolicy(policy, chanURI, cspSpecCompliant);
#ifdef PR_LOGGING
        {
          PR_LOG(gCspPRLog, PR_LOG_DEBUG,
                 ("CSP refined with policy: \"%s\"",
                  NS_ConvertUTF16toUTF8(policy).get()));
        }
#endif
    }
  }

  // ----- if there's a report-only CSP header, apply it
  if (( cspSpecCompliant && !cspROHeaderValue.IsEmpty()) ||
      (!cspSpecCompliant && !cspOldROHeaderValue.IsEmpty())) {
    // post a warning and skip report-only CSP when both read only and regular
    // CSP policies are present since CSP only allows one policy and it can't
    // be partially report-only.
    if (applyAppDefaultCSP || applyCSPFromHeader) {
      mCSPWebConsoleErrorQueue.Add("ReportOnlyCSPIgnored");
#ifdef PR_LOGGING
      PR_LOG(gCspPRLog, PR_LOG_DEBUG,
              ("Skipped report-only CSP init for document %p because another, enforced policy is set", this));
#endif
    } else {
      // we can apply the report-only policy because there's no other CSP
      // applied.
      csp->SetReportOnlyMode(true);

      // Need to tokenize the header value since multiple headers could be
      // concatenated into one comma-separated list of policies.
      // See RFC2616 section 4.2 (last paragraph)
      nsCharSeparatedTokenizer tokenizer(cspSpecCompliant ?
                                         cspROHeaderValue :
                                         cspOldROHeaderValue, ',');
      while (tokenizer.hasMoreTokens()) {
        const nsSubstring& policy = tokenizer.nextToken();
        csp->RefinePolicy(policy, chanURI, cspSpecCompliant);
#ifdef PR_LOGGING
        {
          PR_LOG(gCspPRLog, PR_LOG_DEBUG,
                  ("CSP (report-only) refined with policy: \"%s\"",
                    NS_ConvertUTF16toUTF8(policy).get()));
        }
#endif
      }
    }
  }

  // ----- Enforce frame-ancestor policy on any applied policies
  nsCOMPtr<nsIDocShell> docShell = do_QueryReferent(mDocumentContainer);
  if (docShell) {
    bool safeAncestry = false;

    // PermitsAncestry sends violation reports when necessary
    rv = csp->PermitsAncestry(docShell, &safeAncestry);
    NS_ENSURE_SUCCESS(rv, rv);

    if (!safeAncestry) {
#ifdef PR_LOGGING
      PR_LOG(gCspPRLog, PR_LOG_DEBUG,
              ("CSP doesn't like frame's ancestry, not loading."));
#endif
      // stop!  ERROR page!
      aChannel->Cancel(NS_ERROR_CSP_FRAME_ANCESTOR_VIOLATION);
    }
  }

  if (csp) {
    // Copy into principal
    nsIPrincipal* principal = GetPrincipal();
    principal->SetCsp(csp);
#ifdef PR_LOGGING
    PR_LOG(gCspPRLog, PR_LOG_DEBUG,
           ("Inserted CSP into principal %p", principal));
#endif
  }

  return NS_OK;
}

void
nsDocument::StopDocumentLoad()
{
  if (mParser) {
    mParserAborted = true;
    mParser->Terminate();
  }
}

void
nsDocument::SetDocumentURI(nsIURI* aURI)
{
  nsCOMPtr<nsIURI> oldBase = GetDocBaseURI();
  mDocumentURI = NS_TryToMakeImmutable(aURI);
  nsIURI* newBase = GetDocBaseURI();

  bool equalBases = false;
  // Changing just the ref of a URI does not change how relative URIs would
  // resolve wrt to it, so we can treat the bases as equal as long as they're
  // equal ignoring the ref.
  if (oldBase && newBase) {
    oldBase->EqualsExceptRef(newBase, &equalBases);
  }
  else {
    equalBases = !oldBase && !newBase;
  }

  // If this is the first time we're setting the document's URI, set the
  // document's original URI.
  if (!mOriginalURI)
    mOriginalURI = mDocumentURI;

  // If changing the document's URI changed the base URI of the document, we
  // need to refresh the hrefs of all the links on the page.
  if (!equalBases) {
    RefreshLinkHrefs();
  }
}

NS_IMETHODIMP
nsDocument::GetLastModified(nsAString& aLastModified)
{
  nsIDocument::GetLastModified(aLastModified);
  return NS_OK;
}

void
nsIDocument::GetLastModified(nsAString& aLastModified) const
{
  if (!mLastModified.IsEmpty()) {
    aLastModified.Assign(mLastModified);
  } else {
    // If we for whatever reason failed to find the last modified time
    // (or even the current time), fall back to what NS4.x returned.
    aLastModified.Assign(NS_LITERAL_STRING("01/01/1970 00:00:00"));
  }
}

void
nsDocument::AddToNameTable(Element *aElement, nsIAtom* aName)
{
  MOZ_ASSERT(nsGenericHTMLElement::ShouldExposeNameAsHTMLDocumentProperty(aElement),
             "Only put elements that need to be exposed as document['name'] in "
             "the named table.");

  nsIdentifierMapEntry *entry =
    mIdentifierMap.PutEntry(nsDependentAtomString(aName));

  // Null for out-of-memory
  if (entry) {
    if (!entry->HasNameElement() &&
        !entry->HasIdElementExposedAsHTMLDocumentProperty()) {
      ++mExpandoAndGeneration.generation;
    }
    entry->AddNameElement(this, aElement);
  }
}

void
nsDocument::RemoveFromNameTable(Element *aElement, nsIAtom* aName)
{
  // Speed up document teardown
  if (mIdentifierMap.Count() == 0)
    return;

  nsIdentifierMapEntry *entry =
    mIdentifierMap.GetEntry(nsDependentAtomString(aName));
  if (!entry) // Could be false if the element was anonymous, hence never added
    return;

  entry->RemoveNameElement(aElement);
  if (!entry->HasNameElement() &&
      !entry->HasIdElementExposedAsHTMLDocumentProperty()) {
    ++mExpandoAndGeneration.generation;
  }
}

void
nsDocument::AddToIdTable(Element *aElement, nsIAtom* aId)
{
  nsIdentifierMapEntry *entry =
    mIdentifierMap.PutEntry(nsDependentAtomString(aId));

  if (entry) { /* True except on OOM */
    if (nsGenericHTMLElement::ShouldExposeIdAsHTMLDocumentProperty(aElement) &&
        !entry->HasNameElement() &&
        !entry->HasIdElementExposedAsHTMLDocumentProperty()) {
      ++mExpandoAndGeneration.generation;
    }
    entry->AddIdElement(aElement);
  }
}

void
nsDocument::RemoveFromIdTable(Element *aElement, nsIAtom* aId)
{
  NS_ASSERTION(aId, "huhwhatnow?");

  // Speed up document teardown
  if (mIdentifierMap.Count() == 0) {
    return;
  }

  nsIdentifierMapEntry *entry =
    mIdentifierMap.GetEntry(nsDependentAtomString(aId));
  if (!entry) // Can be null for XML elements with changing ids.
    return;

  entry->RemoveIdElement(aElement);
  if (nsGenericHTMLElement::ShouldExposeIdAsHTMLDocumentProperty(aElement) &&
      !entry->HasNameElement() &&
      !entry->HasIdElementExposedAsHTMLDocumentProperty()) {
    ++mExpandoAndGeneration.generation;
  }
  if (entry->IsEmpty()) {
    mIdentifierMap.RawRemoveEntry(entry);
  }
}

nsIPrincipal*
nsDocument::GetPrincipal()
{
  return NodePrincipal();
}

extern bool sDisablePrefetchHTTPSPref;

void
nsDocument::SetPrincipal(nsIPrincipal *aNewPrincipal)
{
  if (aNewPrincipal && mAllowDNSPrefetch && sDisablePrefetchHTTPSPref) {
    nsCOMPtr<nsIURI> uri;
    aNewPrincipal->GetURI(getter_AddRefs(uri));
    bool isHTTPS;
    if (!uri || NS_FAILED(uri->SchemeIs("https", &isHTTPS)) ||
        isHTTPS) {
      mAllowDNSPrefetch = false;
    }
  }
  mNodeInfoManager->SetDocumentPrincipal(aNewPrincipal);
}

NS_IMETHODIMP
nsDocument::GetApplicationCache(nsIApplicationCache **aApplicationCache)
{
  NS_IF_ADDREF(*aApplicationCache = mApplicationCache);

  return NS_OK;
}

NS_IMETHODIMP
nsDocument::SetApplicationCache(nsIApplicationCache *aApplicationCache)
{
  mApplicationCache = aApplicationCache;

  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetContentType(nsAString& aContentType)
{
  CopyUTF8toUTF16(GetContentTypeInternal(), aContentType);

  return NS_OK;
}

void
nsDocument::SetContentType(const nsAString& aContentType)
{
  NS_ASSERTION(GetContentTypeInternal().IsEmpty() ||
               GetContentTypeInternal().Equals(NS_ConvertUTF16toUTF8(aContentType)),
               "Do you really want to change the content-type?");

  SetContentTypeInternal(NS_ConvertUTF16toUTF8(aContentType));
}

nsresult
nsDocument::GetAllowPlugins(bool * aAllowPlugins)
{
  // First, we ask our docshell if it allows plugins.
  nsCOMPtr<nsIDocShell> docShell = do_QueryReferent(mDocumentContainer);

  if (docShell) {
    docShell->GetAllowPlugins(aAllowPlugins);

    // If the docshell allows plugins, we check whether
    // we are sandboxed and plugins should not be allowed.
    if (*aAllowPlugins)
      *aAllowPlugins = !(mSandboxFlags & SANDBOXED_PLUGINS);
  }

  return NS_OK;
}

already_AddRefed<UndoManager>
nsDocument::GetUndoManager()
{
  Element* rootElement = GetRootElement();
  if (!rootElement) {
    return nullptr;
  }

  if (!mUndoManager) {
    mUndoManager = new UndoManager(rootElement);
  }

  nsRefPtr<UndoManager> undoManager = mUndoManager;
  return undoManager.forget();
}

/* Return true if the document is in the focused top-level window, and is an
 * ancestor of the focused DOMWindow. */
NS_IMETHODIMP
nsDocument::HasFocus(bool* aResult)
{
  ErrorResult rv;
  *aResult = nsIDocument::HasFocus(rv);
  return rv.ErrorCode();
}

bool
nsIDocument::HasFocus(ErrorResult& rv) const
{
  nsIFocusManager* fm = nsFocusManager::GetFocusManager();
  if (!fm) {
    rv.Throw(NS_ERROR_NOT_AVAILABLE);
    return false;
  }

  // Is there a focused DOMWindow?
  nsCOMPtr<nsIDOMWindow> focusedWindow;
  fm->GetFocusedWindow(getter_AddRefs(focusedWindow));
  if (!focusedWindow) {
    return false;
  }

  // Are we an ancestor of the focused DOMWindow?
  nsCOMPtr<nsIDOMDocument> domDocument;
  focusedWindow->GetDocument(getter_AddRefs(domDocument));
  nsCOMPtr<nsIDocument> document = do_QueryInterface(domDocument);

  for (nsIDocument* currentDoc = document; currentDoc;
       currentDoc = currentDoc->GetParentDocument()) {
    if (currentDoc == this) {
      // Yes, we are an ancestor
      return true;
    }
  }

  return false;
}

NS_IMETHODIMP
nsDocument::GetReferrer(nsAString& aReferrer)
{
  nsIDocument::GetReferrer(aReferrer);
  return NS_OK;
}

void
nsIDocument::GetReferrer(nsAString& aReferrer) const
{
  if (mIsSrcdocDocument && mParentDocument)
      mParentDocument->GetReferrer(aReferrer);
  else
    CopyUTF8toUTF16(mReferrer, aReferrer);
}

nsresult
nsIDocument::GetSrcdocData(nsAString &aSrcdocData)
{
  if (mIsSrcdocDocument) {
    nsCOMPtr<nsIInputStreamChannel> inStrmChan = do_QueryInterface(mChannel);
    if (inStrmChan) {
      return inStrmChan->GetSrcdocData(aSrcdocData);
    }
  }
  aSrcdocData = NullString();
  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetActiveElement(nsIDOMElement **aElement)
{
  nsCOMPtr<nsIDOMElement> el(do_QueryInterface(nsIDocument::GetActiveElement()));
  el.forget(aElement);
  return NS_OK;
}

Element*
nsIDocument::GetActiveElement()
{
  // Get the focused element.
  nsCOMPtr<nsPIDOMWindow> window = GetWindow();
  if (window) {
    nsCOMPtr<nsPIDOMWindow> focusedWindow;
    nsIContent* focusedContent =
      nsFocusManager::GetFocusedDescendant(window, false,
                                           getter_AddRefs(focusedWindow));
    // be safe and make sure the element is from this document
    if (focusedContent && focusedContent->OwnerDoc() == this) {
      if (focusedContent->ChromeOnlyAccess()) {
        focusedContent = focusedContent->FindFirstNonChromeOnlyAccessContent();
      }
      if (focusedContent) {
        return focusedContent->AsElement();
      }
    }
  }

  // No focused element anywhere in this document.  Try to get the BODY.
  nsRefPtr<nsHTMLDocument> htmlDoc = AsHTMLDocument();
  if (htmlDoc) {
    // Because of IE compatibility, return null when html document doesn't have
    // a body.
    return htmlDoc->GetBody();
  }

  // If we couldn't get a BODY, return the root element.
  return GetDocumentElement();
}

NS_IMETHODIMP
nsDocument::GetCurrentScript(nsIDOMElement **aElement)
{
  nsCOMPtr<nsIDOMElement> el(do_QueryInterface(nsIDocument::GetCurrentScript()));
  el.forget(aElement);
  return NS_OK;
}

Element*
nsIDocument::GetCurrentScript()
{
  nsCOMPtr<Element> el(do_QueryInterface(ScriptLoader()->GetCurrentScript()));
  return el;
}

NS_IMETHODIMP
nsDocument::ElementFromPoint(float aX, float aY, nsIDOMElement** aReturn)
{
  Element* el = nsIDocument::ElementFromPoint(aX, aY);
  nsCOMPtr<nsIDOMElement> retval = do_QueryInterface(el);
  retval.forget(aReturn);
  return NS_OK;
}

Element*
nsIDocument::ElementFromPoint(float aX, float aY)
{
  return ElementFromPointHelper(aX, aY, false, true);
}

Element*
nsDocument::ElementFromPointHelper(float aX, float aY,
                                   bool aIgnoreRootScrollFrame,
                                   bool aFlushLayout)
{
  // As per the the spec, we return null if either coord is negative
  if (!aIgnoreRootScrollFrame && (aX < 0 || aY < 0)) {
    return nullptr;
  }

  nscoord x = nsPresContext::CSSPixelsToAppUnits(aX);
  nscoord y = nsPresContext::CSSPixelsToAppUnits(aY);
  nsPoint pt(x, y);

  // Make sure the layout information we get is up-to-date, and
  // ensure we get a root frame (for everything but XUL)
  if (aFlushLayout)
    FlushPendingNotifications(Flush_Layout);

  nsIPresShell *ps = GetShell();
  if (!ps) {
    return nullptr;
  }
  nsIFrame *rootFrame = ps->GetRootFrame();

  // XUL docs, unlike HTML, have no frame tree until everything's done loading
  if (!rootFrame) {
    return nullptr; // return null to premature XUL callers as a reminder to wait
  }

  nsIFrame *ptFrame = nsLayoutUtils::GetFrameForPoint(rootFrame, pt, true,
                                                      aIgnoreRootScrollFrame);
  if (!ptFrame) {
    return nullptr;
  }

  nsIContent* elem = GetContentInThisDocument(ptFrame);
  if (elem && !elem->IsElement()) {
    elem = elem->GetParent();
  }
  return elem ? elem->AsElement() : nullptr;
}

nsresult
nsDocument::NodesFromRectHelper(float aX, float aY,
                                float aTopSize, float aRightSize,
                                float aBottomSize, float aLeftSize,
                                bool aIgnoreRootScrollFrame,
                                bool aFlushLayout,
                                nsIDOMNodeList** aReturn)
{
  NS_ENSURE_ARG_POINTER(aReturn);

  nsSimpleContentList* elements = new nsSimpleContentList(this);
  NS_ADDREF(elements);
  *aReturn = elements;

  // Following the same behavior of elementFromPoint,
  // we don't return anything if either coord is negative
  if (!aIgnoreRootScrollFrame && (aX < 0 || aY < 0))
    return NS_OK;

  nscoord x = nsPresContext::CSSPixelsToAppUnits(aX - aLeftSize);
  nscoord y = nsPresContext::CSSPixelsToAppUnits(aY - aTopSize);
  nscoord w = nsPresContext::CSSPixelsToAppUnits(aLeftSize + aRightSize) + 1;
  nscoord h = nsPresContext::CSSPixelsToAppUnits(aTopSize + aBottomSize) + 1;

  nsRect rect(x, y, w, h);

  // Make sure the layout information we get is up-to-date, and
  // ensure we get a root frame (for everything but XUL)
  if (aFlushLayout) {
    FlushPendingNotifications(Flush_Layout);
  }

  nsIPresShell *ps = GetShell();
  NS_ENSURE_STATE(ps);
  nsIFrame *rootFrame = ps->GetRootFrame();

  // XUL docs, unlike HTML, have no frame tree until everything's done loading
  if (!rootFrame)
    return NS_OK; // return nothing to premature XUL callers as a reminder to wait

  nsAutoTArray<nsIFrame*,8> outFrames;
  nsLayoutUtils::GetFramesForArea(rootFrame, rect, outFrames,
                                  true, aIgnoreRootScrollFrame);

  // Used to filter out repeated elements in sequence.
  nsIContent* lastAdded = nullptr;

  for (uint32_t i = 0; i < outFrames.Length(); i++) {
    nsIContent* node = GetContentInThisDocument(outFrames[i]);

    if (node && !node->IsElement() && !node->IsNodeOfType(nsINode::eTEXT)) {
      // We have a node that isn't an element or a text node,
      // use its parent content instead.
      node = node->GetParent();
    }
    if (node && node != lastAdded) {
      elements->AppendElement(node);
      lastAdded = node;
    }
  }

  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetElementsByClassName(const nsAString& aClasses,
                                   nsIDOMNodeList** aReturn)
{
  *aReturn = nsIDocument::GetElementsByClassName(aClasses).get();
  return NS_OK;
}

already_AddRefed<nsContentList>
nsIDocument::GetElementsByClassName(const nsAString& aClasses)
{
  return nsContentUtils::GetElementsByClassName(this, aClasses);
}

NS_IMETHODIMP
nsDocument::ReleaseCapture()
{
  nsIDocument::ReleaseCapture();
  return NS_OK;
}

void
nsIDocument::ReleaseCapture() const
{
  // only release the capture if the caller can access it. This prevents a
  // page from stopping a scrollbar grab for example.
  nsCOMPtr<nsINode> node = nsIPresShell::GetCapturingContent();
  if (node && nsContentUtils::CanCallerAccess(node)) {
    nsIPresShell::SetCapturingContent(nullptr, 0);
  }
}

nsresult
nsDocument::SetBaseURI(nsIURI* aURI)
{
  if (!aURI && !mDocumentBaseURI) {
    return NS_OK;
  }

  // Don't do anything if the URI wasn't actually changed.
  if (aURI && mDocumentBaseURI) {
    bool equalBases = false;
    mDocumentBaseURI->Equals(aURI, &equalBases);
    if (equalBases) {
      return NS_OK;
    }
  }

  if (aURI) {
    mDocumentBaseURI = NS_TryToMakeImmutable(aURI);
  } else {
    mDocumentBaseURI = nullptr;
  }
  RefreshLinkHrefs();

  return NS_OK;
}

void
nsDocument::GetBaseTarget(nsAString &aBaseTarget)
{
  aBaseTarget = mBaseTarget;
}

void
nsDocument::SetDocumentCharacterSet(const nsACString& aCharSetID)
{
  if (!mCharacterSet.Equals(aCharSetID)) {
    mCharacterSet = aCharSetID;

#ifdef DEBUG
    nsAutoCString canonicalName;
    nsCharsetAlias::GetPreferred(aCharSetID, canonicalName);
    NS_ASSERTION(canonicalName.Equals(aCharSetID),
                 "charset name must be canonical");
#endif

    int32_t n = mCharSetObservers.Length();

    for (int32_t i = 0; i < n; i++) {
      nsIObserver* observer = mCharSetObservers.ElementAt(i);

      observer->Observe(static_cast<nsIDocument *>(this), "charset",
                        NS_ConvertASCIItoUTF16(aCharSetID).get());
    }
  }
}

nsresult
nsDocument::AddCharSetObserver(nsIObserver* aObserver)
{
  NS_ENSURE_ARG_POINTER(aObserver);

  NS_ENSURE_TRUE(mCharSetObservers.AppendElement(aObserver), NS_ERROR_FAILURE);

  return NS_OK;
}

void
nsDocument::RemoveCharSetObserver(nsIObserver* aObserver)
{
  mCharSetObservers.RemoveElement(aObserver);
}

void
nsDocument::GetHeaderData(nsIAtom* aHeaderField, nsAString& aData) const
{
  aData.Truncate();
  const nsDocHeaderData* data = mHeaderData;
  while (data) {
    if (data->mField == aHeaderField) {
      aData = data->mData;

      break;
    }
    data = data->mNext;
  }
}

void
nsDocument::SetHeaderData(nsIAtom* aHeaderField, const nsAString& aData)
{
  if (!aHeaderField) {
    NS_ERROR("null headerField");
    return;
  }

  if (!mHeaderData) {
    if (!aData.IsEmpty()) { // don't bother storing empty string
      mHeaderData = new nsDocHeaderData(aHeaderField, aData);
    }
  }
  else {
    nsDocHeaderData* data = mHeaderData;
    nsDocHeaderData** lastPtr = &mHeaderData;
    bool found = false;
    do {  // look for existing and replace
      if (data->mField == aHeaderField) {
        if (!aData.IsEmpty()) {
          data->mData.Assign(aData);
        }
        else {  // don't store empty string
          *lastPtr = data->mNext;
          data->mNext = nullptr;
          delete data;
        }
        found = true;

        break;
      }
      lastPtr = &(data->mNext);
      data = *lastPtr;
    } while (data);

    if (!aData.IsEmpty() && !found) {
      // didn't find, append
      *lastPtr = new nsDocHeaderData(aHeaderField, aData);
    }
  }

  if (aHeaderField == nsGkAtoms::headerContentLanguage) {
    CopyUTF16toUTF8(aData, mContentLanguage);
  }

  if (aHeaderField == nsGkAtoms::headerDefaultStyle) {
    // Only mess with our stylesheets if we don't have a lastStyleSheetSet, per
    // spec.
    if (DOMStringIsNull(mLastStyleSheetSet)) {
      // Calling EnableStyleSheetsForSetInternal, not SetSelectedStyleSheetSet,
      // per spec.  The idea here is that we're changing our preferred set and
      // that shouldn't change the value of lastStyleSheetSet.  Also, we're
      // using the Internal version so we can update the CSSLoader and not have
      // to worry about null strings.
      EnableStyleSheetsForSetInternal(aData, true);
    }
  }

  if (aHeaderField == nsGkAtoms::refresh) {
    // We get into this code before we have a script global yet, so get to
    // our container via mDocumentContainer.
    nsCOMPtr<nsIRefreshURI> refresher = do_QueryReferent(mDocumentContainer);
    if (refresher) {
      // Note: using mDocumentURI instead of mBaseURI here, for consistency
      // (used to just use the current URI of our webnavigation, but that
      // should really be the same thing).  Note that this code can run
      // before the current URI of the webnavigation has been updated, so we
      // can't assert equality here.
      refresher->SetupRefreshURIFromHeader(mDocumentURI, NodePrincipal(),
                                           NS_ConvertUTF16toUTF8(aData));
    }
  }

  if (aHeaderField == nsGkAtoms::headerDNSPrefetchControl &&
      mAllowDNSPrefetch) {
    // Chromium treats any value other than 'on' (case insensitive) as 'off'.
    mAllowDNSPrefetch = aData.IsEmpty() || aData.LowerCaseEqualsLiteral("on");
  }

  if (aHeaderField == nsGkAtoms::viewport ||
      aHeaderField == nsGkAtoms::handheldFriendly ||
      aHeaderField == nsGkAtoms::viewport_minimum_scale ||
      aHeaderField == nsGkAtoms::viewport_maximum_scale ||
      aHeaderField == nsGkAtoms::viewport_initial_scale ||
      aHeaderField == nsGkAtoms::viewport_height ||
      aHeaderField == nsGkAtoms::viewport_width ||
      aHeaderField ==  nsGkAtoms::viewport_user_scalable) {
    mViewportType = Unknown;
  }
}

void
nsDocument::TryChannelCharset(nsIChannel *aChannel,
                              int32_t& aCharsetSource,
                              nsACString& aCharset,
                              nsHtml5TreeOpExecutor* aExecutor)
{
  if (aChannel) {
    nsAutoCString charsetVal;
    nsresult rv = aChannel->GetContentCharset(charsetVal);
    if (NS_SUCCEEDED(rv)) {
      nsAutoCString preferred;
      if(EncodingUtils::FindEncodingForLabel(charsetVal, preferred)) {
        aCharset = preferred;
        aCharsetSource = kCharsetFromChannel;
        return;
      } else if (aExecutor && !charsetVal.IsEmpty()) {
        aExecutor->ComplainAboutBogusProtocolCharset(this);
      }
    }
  }
}

already_AddRefed<nsIPresShell>
nsDocument::CreateShell(nsPresContext* aContext, nsViewManager* aViewManager,
                        nsStyleSet* aStyleSet)
{
  // Don't add anything here.  Add it to |doCreateShell| instead.
  // This exists so that subclasses can pass other values for the 4th
  // parameter some of the time.
  return doCreateShell(aContext, aViewManager, aStyleSet,
                       eCompatibility_FullStandards);
}

already_AddRefed<nsIPresShell>
nsDocument::doCreateShell(nsPresContext* aContext,
                          nsViewManager* aViewManager, nsStyleSet* aStyleSet,
                          nsCompatibility aCompatMode)
{
  NS_ASSERTION(!mPresShell, "We have a presshell already!");

  NS_ENSURE_FALSE(GetBFCacheEntry(), nullptr);

  FillStyleSet(aStyleSet);

  nsRefPtr<PresShell> shell = new PresShell;
  shell->Init(this, aContext, aViewManager, aStyleSet, aCompatMode);

  // Note: we don't hold a ref to the shell (it holds a ref to us)
  mPresShell = shell;

  mExternalResourceMap.ShowViewers();

  MaybeRescheduleAnimationFrameNotifications();

  return shell.forget();
}

void
nsDocument::MaybeRescheduleAnimationFrameNotifications()
{
  if (!mPresShell || !IsEventHandlingEnabled()) {
    // bail out for now, until one of those conditions changes
    return;
  }

  nsRefreshDriver* rd = mPresShell->GetPresContext()->RefreshDriver();
  if (!mFrameRequestCallbacks.IsEmpty()) {
    rd->ScheduleFrameRequestCallbacks(this);
  }
}

void
nsIDocument::TakeFrameRequestCallbacks(FrameRequestCallbackList& aCallbacks)
{
  aCallbacks.AppendElements(mFrameRequestCallbacks);
  mFrameRequestCallbacks.Clear();
}

PLDHashOperator RequestDiscardEnumerator(imgIRequest* aKey,
                                         uint32_t aData,
                                         void* userArg)
{
  aKey->RequestDiscard();
  return PL_DHASH_NEXT;
}

void
nsDocument::DeleteShell()
{
  mExternalResourceMap.HideViewers();
  if (IsEventHandlingEnabled()) {
    RevokeAnimationFrameNotifications();
  }

  // When our shell goes away, request that all our images be immediately
  // discarded, so we don't carry around decoded image data for a document we
  // no longer intend to paint.
  mImageTracker.EnumerateRead(RequestDiscardEnumerator, nullptr);

  mPresShell = nullptr;
}

void
nsDocument::RevokeAnimationFrameNotifications()
{
  if (!mFrameRequestCallbacks.IsEmpty()) {
    mPresShell->GetPresContext()->RefreshDriver()->
      RevokeFrameRequestCallbacks(this);
  }
}

static void
SubDocClearEntry(PLDHashTable *table, PLDHashEntryHdr *entry)
{
  SubDocMapEntry *e = static_cast<SubDocMapEntry *>(entry);

  NS_RELEASE(e->mKey);
  if (e->mSubDocument) {
    e->mSubDocument->SetParentDocument(nullptr);
    NS_RELEASE(e->mSubDocument);
  }
}

static bool
SubDocInitEntry(PLDHashTable *table, PLDHashEntryHdr *entry, const void *key)
{
  SubDocMapEntry *e =
    const_cast<SubDocMapEntry *>
              (static_cast<const SubDocMapEntry *>(entry));

  e->mKey = const_cast<Element*>(static_cast<const Element*>(key));
  NS_ADDREF(e->mKey);

  e->mSubDocument = nullptr;
  return true;
}

nsresult
nsDocument::SetSubDocumentFor(Element* aElement, nsIDocument* aSubDoc)
{
  NS_ENSURE_TRUE(aElement, NS_ERROR_UNEXPECTED);

  if (!aSubDoc) {
    // aSubDoc is nullptr, remove the mapping

    if (mSubDocuments) {
      SubDocMapEntry *entry =
        static_cast<SubDocMapEntry*>
                   (PL_DHashTableOperate(mSubDocuments, aElement,
                                         PL_DHASH_LOOKUP));

      if (PL_DHASH_ENTRY_IS_BUSY(entry)) {
        PL_DHashTableRawRemove(mSubDocuments, entry);
      }
    }
  } else {
    if (!mSubDocuments) {
      // Create a new hashtable

      static PLDHashTableOps hash_table_ops =
      {
        PL_DHashAllocTable,
        PL_DHashFreeTable,
        PL_DHashVoidPtrKeyStub,
        PL_DHashMatchEntryStub,
        PL_DHashMoveEntryStub,
        SubDocClearEntry,
        PL_DHashFinalizeStub,
        SubDocInitEntry
      };

      mSubDocuments = PL_NewDHashTable(&hash_table_ops, nullptr,
                                       sizeof(SubDocMapEntry), 16);
      if (!mSubDocuments) {
        return NS_ERROR_OUT_OF_MEMORY;
      }
    }

    // Add a mapping to the hash table
    SubDocMapEntry *entry =
      static_cast<SubDocMapEntry*>
                 (PL_DHashTableOperate(mSubDocuments, aElement,
                                       PL_DHASH_ADD));

    if (!entry) {
      return NS_ERROR_OUT_OF_MEMORY;
    }

    if (entry->mSubDocument) {
      entry->mSubDocument->SetParentDocument(nullptr);

      // Release the old sub document
      NS_RELEASE(entry->mSubDocument);
    }

    entry->mSubDocument = aSubDoc;
    NS_ADDREF(entry->mSubDocument);

    aSubDoc->SetParentDocument(this);
  }

  return NS_OK;
}

nsIDocument*
nsDocument::GetSubDocumentFor(nsIContent *aContent) const
{
  if (mSubDocuments && aContent->IsElement()) {
    SubDocMapEntry *entry =
      static_cast<SubDocMapEntry*>
                 (PL_DHashTableOperate(mSubDocuments, aContent->AsElement(),
                                       PL_DHASH_LOOKUP));

    if (PL_DHASH_ENTRY_IS_BUSY(entry)) {
      return entry->mSubDocument;
    }
  }

  return nullptr;
}

static PLDHashOperator
FindContentEnumerator(PLDHashTable *table, PLDHashEntryHdr *hdr,
                      uint32_t number, void *arg)
{
  SubDocMapEntry *entry = static_cast<SubDocMapEntry*>(hdr);
  FindContentData *data = static_cast<FindContentData*>(arg);

  if (entry->mSubDocument == data->mSubDocument) {
    data->mResult = entry->mKey;

    return PL_DHASH_STOP;
  }

  return PL_DHASH_NEXT;
}

Element*
nsDocument::FindContentForSubDocument(nsIDocument *aDocument) const
{
  NS_ENSURE_TRUE(aDocument, nullptr);

  if (!mSubDocuments) {
    return nullptr;
  }

  FindContentData data(aDocument);
  PL_DHashTableEnumerate(mSubDocuments, FindContentEnumerator, &data);

  return data.mResult;
}

bool
nsDocument::IsNodeOfType(uint32_t aFlags) const
{
    return !(aFlags & ~eDOCUMENT);
}

Element*
nsIDocument::GetRootElement() const
{
  return (mCachedRootElement && mCachedRootElement->GetParentNode() == this) ?
         mCachedRootElement : GetRootElementInternal();
}

Element*
nsDocument::GetRootElementInternal() const
{
  // Loop backwards because any non-elements, such as doctypes and PIs
  // are likely to appear before the root element.
  uint32_t i;
  for (i = mChildren.ChildCount(); i > 0; --i) {
    nsIContent* child = mChildren.ChildAt(i - 1);
    if (child->IsElement()) {
      const_cast<nsDocument*>(this)->mCachedRootElement = child->AsElement();
      return child->AsElement();
    }
  }

  const_cast<nsDocument*>(this)->mCachedRootElement = nullptr;
  return nullptr;
}

nsIContent *
nsDocument::GetChildAt(uint32_t aIndex) const
{
  return mChildren.GetSafeChildAt(aIndex);
}

int32_t
nsDocument::IndexOf(const nsINode* aPossibleChild) const
{
  return mChildren.IndexOfChild(aPossibleChild);
}

uint32_t
nsDocument::GetChildCount() const
{
  return mChildren.ChildCount();
}

nsIContent * const *
nsDocument::GetChildArray(uint32_t* aChildCount) const
{
  return mChildren.GetChildArray(aChildCount);
}


nsresult
nsDocument::InsertChildAt(nsIContent* aKid, uint32_t aIndex,
                          bool aNotify)
{
  if (aKid->IsElement() && GetRootElement()) {
    NS_ERROR("Inserting element child when we already have one");
    return NS_ERROR_DOM_HIERARCHY_REQUEST_ERR;
  }

  return doInsertChildAt(aKid, aIndex, aNotify, mChildren);
}

nsresult
nsDocument::AppendChildTo(nsIContent* aKid, bool aNotify)
{
  // Make sure to _not_ call the subclass InsertChildAt here.  If
  // subclasses wanted to hook into this stuff, they would have
  // overridden AppendChildTo.
  // XXXbz maybe this should just be a non-virtual method on nsINode?
  // Feels that way to me...
  return nsDocument::InsertChildAt(aKid, GetChildCount(), aNotify);
}

void
nsDocument::RemoveChildAt(uint32_t aIndex, bool aNotify)
{
  nsCOMPtr<nsIContent> oldKid = GetChildAt(aIndex);
  if (!oldKid) {
    return;
  }

  if (oldKid->IsElement()) {
    // Destroy the link map up front before we mess with the child list.
    DestroyElementMaps();
  }

  doRemoveChildAt(aIndex, aNotify, oldKid, mChildren);
  mCachedRootElement = nullptr;
}

int32_t
nsDocument::GetNumberOfStyleSheets() const
{
  return mStyleSheets.Count();
}

nsIStyleSheet*
nsDocument::GetStyleSheetAt(int32_t aIndex) const
{
  NS_ENSURE_TRUE(0 <= aIndex && aIndex < mStyleSheets.Count(), nullptr);
  return mStyleSheets[aIndex];
}

int32_t
nsDocument::GetIndexOfStyleSheet(nsIStyleSheet* aSheet) const
{
  return mStyleSheets.IndexOf(aSheet);
}

void
nsDocument::AddStyleSheetToStyleSets(nsIStyleSheet* aSheet)
{
  nsCOMPtr<nsIPresShell> shell = GetShell();
  if (shell) {
    shell->StyleSet()->AddDocStyleSheet(aSheet, this);
  }
}

#define DO_STYLESHEET_NOTIFICATION(createFunc, concreteInterface, initMethod, type, ...) \
  do {                                                                  \
    nsCOMPtr<nsIDOMEvent> event;                                        \
    nsresult rv = createFunc(getter_AddRefs(event), this,               \
                             mPresShell ?                               \
                             mPresShell->GetPresContext() : nullptr,    \
                             nullptr);                                  \
    if (NS_FAILED(rv)) {                                                \
      return;                                                           \
    }                                                                   \
    nsCOMPtr<nsIDOMCSSStyleSheet> cssSheet(do_QueryInterface(aSheet));  \
    if (!cssSheet) {                                                    \
      return;                                                           \
    }                                                                   \
    nsCOMPtr<concreteInterface> ssEvent(do_QueryInterface(event));      \
    MOZ_ASSERT(ssEvent);                                                \
    ssEvent->initMethod(NS_LITERAL_STRING(type), true, true,            \
                        cssSheet, __VA_ARGS__);                         \
    event->SetTrusted(true);                                            \
    event->SetTarget(this);                                             \
    nsRefPtr<nsAsyncDOMEvent> asyncEvent = new nsAsyncDOMEvent(this, event); \
    asyncEvent->mDispatchChromeOnly = true;                             \
    asyncEvent->PostDOMEvent();                                         \
  } while (0);

void
nsDocument::NotifyStyleSheetAdded(nsIStyleSheet* aSheet, bool aDocumentSheet)
{
  NS_DOCUMENT_NOTIFY_OBSERVERS(StyleSheetAdded, (this, aSheet, aDocumentSheet));

  if (StyleSheetChangeEventsEnabled()) {
    DO_STYLESHEET_NOTIFICATION(NS_NewDOMStyleSheetChangeEvent,
                               nsIDOMStyleSheetChangeEvent,
                               InitStyleSheetChangeEvent,
                               "StyleSheetAdded",
                               aDocumentSheet);
  }
}

void
nsDocument::NotifyStyleSheetRemoved(nsIStyleSheet* aSheet, bool aDocumentSheet)
{
  NS_DOCUMENT_NOTIFY_OBSERVERS(StyleSheetRemoved, (this, aSheet, aDocumentSheet));

  if (StyleSheetChangeEventsEnabled()) {
    DO_STYLESHEET_NOTIFICATION(NS_NewDOMStyleSheetChangeEvent,
                               nsIDOMStyleSheetChangeEvent,
                               InitStyleSheetChangeEvent,
                               "StyleSheetRemoved",
                               aDocumentSheet);
  }
}

void
nsDocument::AddStyleSheet(nsIStyleSheet* aSheet)
{
  NS_PRECONDITION(aSheet, "null arg");
  mStyleSheets.AppendObject(aSheet);
  aSheet->SetOwningDocument(this);

  if (aSheet->IsApplicable()) {
    AddStyleSheetToStyleSets(aSheet);
  }

  NotifyStyleSheetAdded(aSheet, true);
}

void
nsDocument::RemoveStyleSheetFromStyleSets(nsIStyleSheet* aSheet)
{
  nsCOMPtr<nsIPresShell> shell = GetShell();
  if (shell) {
    shell->StyleSet()->RemoveDocStyleSheet(aSheet);
  }
}

void
nsDocument::RemoveStyleSheet(nsIStyleSheet* aSheet)
{
  NS_PRECONDITION(aSheet, "null arg");
  nsCOMPtr<nsIStyleSheet> sheet = aSheet; // hold ref so it won't die too soon

  if (!mStyleSheets.RemoveObject(aSheet)) {
    NS_ASSERTION(mInUnlinkOrDeletion, "stylesheet not found");
    return;
  }

  if (!mIsGoingAway) {
    if (aSheet->IsApplicable()) {
      RemoveStyleSheetFromStyleSets(aSheet);
    }

    NotifyStyleSheetRemoved(aSheet, true);
  }

  aSheet->SetOwningDocument(nullptr);
}

void
nsDocument::UpdateStyleSheets(nsCOMArray<nsIStyleSheet>& aOldSheets,
                              nsCOMArray<nsIStyleSheet>& aNewSheets)
{
  BeginUpdate(UPDATE_STYLE);

  // XXX Need to set the sheet on the ownernode, if any
  NS_PRECONDITION(aOldSheets.Count() == aNewSheets.Count(),
                  "The lists must be the same length!");
  int32_t count = aOldSheets.Count();

  nsCOMPtr<nsIStyleSheet> oldSheet;
  int32_t i;
  for (i = 0; i < count; ++i) {
    oldSheet = aOldSheets[i];

    // First remove the old sheet.
    NS_ASSERTION(oldSheet, "None of the old sheets should be null");
    int32_t oldIndex = mStyleSheets.IndexOf(oldSheet);
    RemoveStyleSheet(oldSheet);  // This does the right notifications

    // Now put the new one in its place.  If it's null, just ignore it.
    nsIStyleSheet* newSheet = aNewSheets[i];
    if (newSheet) {
      mStyleSheets.InsertObjectAt(newSheet, oldIndex);
      newSheet->SetOwningDocument(this);
      if (newSheet->IsApplicable()) {
        AddStyleSheetToStyleSets(newSheet);
      }

      NotifyStyleSheetAdded(newSheet, true);
    }
  }

  EndUpdate(UPDATE_STYLE);
}

void
nsDocument::InsertStyleSheetAt(nsIStyleSheet* aSheet, int32_t aIndex)
{
  NS_PRECONDITION(aSheet, "null ptr");
  mStyleSheets.InsertObjectAt(aSheet, aIndex);

  aSheet->SetOwningDocument(this);

  if (aSheet->IsApplicable()) {
    AddStyleSheetToStyleSets(aSheet);
  }

  NotifyStyleSheetAdded(aSheet, true);
}


void
nsDocument::SetStyleSheetApplicableState(nsIStyleSheet* aSheet,
                                         bool aApplicable)
{
  NS_PRECONDITION(aSheet, "null arg");

  // If we're actually in the document style sheet list
  if (-1 != mStyleSheets.IndexOf(aSheet)) {
    if (aApplicable) {
      AddStyleSheetToStyleSets(aSheet);
    } else {
      RemoveStyleSheetFromStyleSets(aSheet);
    }
  }

  // We have to always notify, since this will be called for sheets
  // that are children of sheets in our style set, as well as some
  // sheets for nsHTMLEditor.

  NS_DOCUMENT_NOTIFY_OBSERVERS(StyleSheetApplicableStateChanged,
                               (this, aSheet, aApplicable));

  if (StyleSheetChangeEventsEnabled()) {
    DO_STYLESHEET_NOTIFICATION(NS_NewDOMStyleSheetApplicableStateChangeEvent,
                               nsIDOMStyleSheetApplicableStateChangeEvent,
                               InitStyleSheetApplicableStateChangeEvent,
                               "StyleSheetApplicableStateChanged",
                               aApplicable);
  }
}

// These three functions are a lot like the implementation of the
// corresponding API for regular stylesheets.

int32_t
nsDocument::GetNumberOfCatalogStyleSheets() const
{
  return mCatalogSheets.Count();
}

nsIStyleSheet*
nsDocument::GetCatalogStyleSheetAt(int32_t aIndex) const
{
  NS_ENSURE_TRUE(0 <= aIndex && aIndex < mCatalogSheets.Count(), nullptr);
  return mCatalogSheets[aIndex];
}

void
nsDocument::AddCatalogStyleSheet(nsCSSStyleSheet* aSheet)
{
  mCatalogSheets.AppendObject(aSheet);
  aSheet->SetOwningDocument(this);
  aSheet->SetOwningNode(this);

  if (aSheet->IsApplicable()) {
    // This is like |AddStyleSheetToStyleSets|, but for an agent sheet.
    nsCOMPtr<nsIPresShell> shell = GetShell();
    if (shell) {
      shell->StyleSet()->AppendStyleSheet(nsStyleSet::eAgentSheet, aSheet);
    }
  }

  NotifyStyleSheetAdded(aSheet, false);
}

void
nsDocument::EnsureCatalogStyleSheet(const char *aStyleSheetURI)
{
  mozilla::css::Loader* cssLoader = CSSLoader();
  if (cssLoader->GetEnabled()) {
    int32_t sheetCount = GetNumberOfCatalogStyleSheets();
    for (int32_t i = 0; i < sheetCount; i++) {
      nsIStyleSheet* sheet = GetCatalogStyleSheetAt(i);
      NS_ASSERTION(sheet, "unexpected null stylesheet in the document");
      if (sheet) {
        nsAutoCString uriStr;
        sheet->GetSheetURI()->GetSpec(uriStr);
        if (uriStr.Equals(aStyleSheetURI))
          return;
      }
    }

    nsCOMPtr<nsIURI> uri;
    NS_NewURI(getter_AddRefs(uri), aStyleSheetURI);
    if (uri) {
      nsRefPtr<nsCSSStyleSheet> sheet;
      cssLoader->LoadSheetSync(uri, true, true, getter_AddRefs(sheet));
      if (sheet) {
        BeginUpdate(UPDATE_STYLE);
        AddCatalogStyleSheet(sheet);
        EndUpdate(UPDATE_STYLE);
      }
    }
  }
}

static nsStyleSet::sheetType
ConvertAdditionalSheetType(nsIDocument::additionalSheetType aType)
{
  switch(aType) {
    case nsIDocument::eAgentSheet:
      return nsStyleSet::eAgentSheet;
    case nsIDocument::eUserSheet:
      return nsStyleSet::eUserSheet;
    case nsIDocument::eAuthorSheet:
      return nsStyleSet::eDocSheet;
    default:
      NS_ASSERTION(false, "wrong type");
      // we must return something although this should never happen
      return nsStyleSet::eSheetTypeCount;
  }
}

static int32_t
FindSheet(const nsCOMArray<nsIStyleSheet>& aSheets, nsIURI* aSheetURI)
{
  for (int32_t i = aSheets.Count() - 1; i >= 0; i-- ) {
    bool bEqual;
    nsIURI* uri = aSheets[i]->GetSheetURI();

    if (uri && NS_SUCCEEDED(uri->Equals(aSheetURI, &bEqual)) && bEqual)
      return i;
  }

  return -1;
}

nsresult
nsDocument::LoadAdditionalStyleSheet(additionalSheetType aType, nsIURI* aSheetURI)
{
  NS_PRECONDITION(aSheetURI, "null arg");

  // Checking if we have loaded this one already.
  if (FindSheet(mAdditionalSheets[aType], aSheetURI) >= 0)
    return NS_ERROR_INVALID_ARG;

  // Loading the sheet sync.
  nsRefPtr<mozilla::css::Loader> loader = new mozilla::css::Loader();

  nsRefPtr<nsCSSStyleSheet> sheet;
  nsresult rv = loader->LoadSheetSync(aSheetURI, aType == eAgentSheet,
    true, getter_AddRefs(sheet));
  NS_ENSURE_SUCCESS(rv, rv);

  mAdditionalSheets[aType].AppendObject(sheet);
  sheet->SetOwningDocument(this);
  MOZ_ASSERT(sheet->IsApplicable());

  BeginUpdate(UPDATE_STYLE);
  nsCOMPtr<nsIPresShell> shell = GetShell();
  if (shell) {
    nsStyleSet::sheetType type = ConvertAdditionalSheetType(aType);
    shell->StyleSet()->AppendStyleSheet(type, sheet);
  }

  // Passing false, so documet.styleSheets.length will not be affected by
  // these additional sheets.
  NotifyStyleSheetAdded(sheet, false);
  EndUpdate(UPDATE_STYLE);

  return NS_OK;
}

void
nsDocument::RemoveAdditionalStyleSheet(additionalSheetType aType, nsIURI* aSheetURI)
{
  MOZ_ASSERT(aSheetURI);

  nsCOMArray<nsIStyleSheet>& sheets = mAdditionalSheets[aType];

  int32_t i = FindSheet(mAdditionalSheets[aType], aSheetURI);
  if (i >= 0) {
    nsCOMPtr<nsIStyleSheet> sheetRef = sheets[i];
    sheets.RemoveObjectAt(i);

    BeginUpdate(UPDATE_STYLE);
    if (!mIsGoingAway) {
      MOZ_ASSERT(sheetRef->IsApplicable());
      nsCOMPtr<nsIPresShell> shell = GetShell();
      if (shell) {
        nsStyleSet::sheetType type = ConvertAdditionalSheetType(aType);
        shell->StyleSet()->RemoveStyleSheet(type, sheetRef);
      }
    }

    // Passing false, so documet.styleSheets.length will not be affected by
    // these additional sheets.
    NotifyStyleSheetRemoved(sheetRef, false);
    EndUpdate(UPDATE_STYLE);

    sheetRef->SetOwningDocument(nullptr);
  }
}

nsIStyleSheet*
nsDocument::FirstAdditionalAuthorSheet()
{
  return mAdditionalSheets[eAuthorSheet].SafeObjectAt(0);
}

nsIGlobalObject*
nsDocument::GetScopeObject() const
{
  nsCOMPtr<nsIGlobalObject> scope(do_QueryReferent(mScopeObject));
  return scope;
}

void
nsDocument::SetScopeObject(nsIGlobalObject* aGlobal)
{
  mScopeObject = do_GetWeakReference(aGlobal);
  if (aGlobal) {
    mHasHadScriptHandlingObject = true;
  }
}

static void
NotifyActivityChanged(nsIContent *aContent, void *aUnused)
{
  nsCOMPtr<nsIDOMHTMLMediaElement> domMediaElem(do_QueryInterface(aContent));
  if (domMediaElem) {
    HTMLMediaElement* mediaElem = static_cast<HTMLMediaElement*>(aContent);
    mediaElem->NotifyOwnerDocumentActivityChanged();
  }
  nsCOMPtr<nsIObjectLoadingContent> objectLoadingContent(do_QueryInterface(aContent));
  if (objectLoadingContent) {
    nsObjectLoadingContent* olc = static_cast<nsObjectLoadingContent*>(objectLoadingContent.get());
    olc->NotifyOwnerDocumentActivityChanged();
  }
}

void
nsIDocument::SetContainer(nsISupports* aContainer)
{
  mDocumentContainer = do_GetWeakReference(aContainer);
  EnumerateFreezableElements(NotifyActivityChanged, nullptr);
  // Get the Docshell
  nsCOMPtr<nsIDocShell> docShell = do_QueryInterface(aContainer);
  if (docShell) {
    int32_t itemType;
    docShell->GetItemType(&itemType);
    // check itemtype
    if (itemType == nsIDocShellTreeItem::typeContent) {
      // check if same type root
      nsCOMPtr<nsIDocShellTreeItem> sameTypeRoot;
      docShell->GetSameTypeRootTreeItem(getter_AddRefs(sameTypeRoot));
      NS_ASSERTION(sameTypeRoot, "No document shell root tree item from document shell tree item!");

      if (sameTypeRoot == docShell) {
        static_cast<nsDocument*>(this)->SetIsTopLevelContentDocument(true);
      }
    }
  }
}

void
nsDocument::SetScriptGlobalObject(nsIScriptGlobalObject *aScriptGlobalObject)
{
#ifdef DEBUG
  {
    nsCOMPtr<nsPIDOMWindow> win(do_QueryInterface(aScriptGlobalObject));

    NS_ASSERTION(!win || win->IsInnerWindow(),
                 "Script global object must be an inner window!");
  }
#endif
  NS_ABORT_IF_FALSE(aScriptGlobalObject || !mAnimationController ||
                    mAnimationController->IsPausedByType(
                        nsSMILTimeContainer::PAUSE_PAGEHIDE |
                        nsSMILTimeContainer::PAUSE_BEGIN),
                    "Clearing window pointer while animations are unpaused");

  if (mScriptGlobalObject && !aScriptGlobalObject) {
    // We're detaching from the window.  We need to grab a pointer to
    // our layout history state now.
    mLayoutHistoryState = GetLayoutHistoryState();

    if (mPresShell && !EventHandlingSuppressed()) {
      RevokeAnimationFrameNotifications();
    }

    // Also make sure to remove our onload blocker now if we haven't done it yet
    if (mOnloadBlockCount != 0) {
      nsCOMPtr<nsILoadGroup> loadGroup = GetDocumentLoadGroup();
      if (loadGroup) {
        loadGroup->RemoveRequest(mOnloadBlocker, nullptr, NS_OK);
      }
    }
  }

  mScriptGlobalObject = aScriptGlobalObject;

  if (aScriptGlobalObject) {
    mHasHadScriptHandlingObject = true;
    mHasHadDefaultView = true;
    // Go back to using the docshell for the layout history state
    mLayoutHistoryState = nullptr;
    mScopeObject = do_GetWeakReference(aScriptGlobalObject);
#ifdef DEBUG
    if (!mWillReparent) {
      // We really shouldn't have a wrapper here but if we do we need to make sure
      // it has the correct parent.
      JSObject *obj = GetWrapperPreserveColor();
      if (obj) {
        JSObject *newScope = aScriptGlobalObject->GetGlobalJSObject();
        NS_ASSERTION(js::GetGlobalForObjectCrossCompartment(obj) == newScope,
                     "Wrong scope, this is really bad!");
      }
    }
#endif

    if (mAllowDNSPrefetch) {
      nsCOMPtr<nsIDocShell> docShell = do_QueryReferent(mDocumentContainer);
      if (docShell) {
#ifdef DEBUG
        nsCOMPtr<nsIWebNavigation> webNav =
          do_GetInterface(aScriptGlobalObject);
        NS_ASSERTION(SameCOMIdentity(webNav, docShell),
                     "Unexpected container or script global?");
#endif
        bool allowDNSPrefetch;
        docShell->GetAllowDNSPrefetch(&allowDNSPrefetch);
        mAllowDNSPrefetch = allowDNSPrefetch;
      }
    }

    MaybeRescheduleAnimationFrameNotifications();
  }

  // Remember the pointer to our window (or lack there of), to avoid
  // having to QI every time it's asked for.
  nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(mScriptGlobalObject);
  mWindow = window;

  // Now that we know what our window is, we can flush the CSP errors to the
  // Web Console.
  FlushCSPWebConsoleErrorQueue();

  // Set our visibility state, but do not fire the event.  This is correct
  // because either we're coming out of bfcache (in which case IsVisible() will
  // still test false at this point and no state change will happen) or we're
  // doing the initial document load and don't want to fire the event for this
  // change.
  mVisibilityState = GetVisibilityState();
}

nsIScriptGlobalObject*
nsDocument::GetScriptHandlingObjectInternal() const
{
  MOZ_ASSERT(!mScriptGlobalObject,
             "Do not call this when mScriptGlobalObject is set!");
  if (mHasHadDefaultView) {
    return nullptr;
  }

  nsCOMPtr<nsIScriptGlobalObject> scriptHandlingObject =
    do_QueryReferent(mScopeObject);
  nsCOMPtr<nsPIDOMWindow> win = do_QueryInterface(scriptHandlingObject);
  if (win) {
    NS_ASSERTION(win->IsInnerWindow(), "Should have inner window here!");
    nsPIDOMWindow* outer = win->GetOuterWindow();
    if (!outer || outer->GetCurrentInnerWindow() != win) {
      NS_WARNING("Wrong inner/outer window combination!");
      return nullptr;
    }
  }
  return scriptHandlingObject;
}
void
nsDocument::SetScriptHandlingObject(nsIScriptGlobalObject* aScriptObject)
{
  NS_ASSERTION(!mScriptGlobalObject ||
               mScriptGlobalObject == aScriptObject,
               "Wrong script object!");
  nsCOMPtr<nsPIDOMWindow> win = do_QueryInterface(aScriptObject);
  NS_ASSERTION(!win || win->IsInnerWindow(), "Should have inner window here!");
  if (aScriptObject) {
    mScopeObject = do_GetWeakReference(aScriptObject);
    mHasHadScriptHandlingObject = true;
    mHasHadDefaultView = false;
  }
}

bool
nsDocument::IsTopLevelContentDocument()
{
  return mIsTopLevelContentDocument;
}

void
nsDocument::SetIsTopLevelContentDocument(bool aIsTopLevelContentDocument)
{
  mIsTopLevelContentDocument = aIsTopLevelContentDocument;
}

nsPIDOMWindow *
nsDocument::GetWindowInternal() const
{
  MOZ_ASSERT(!mWindow, "This should not be called when mWindow is not null!");
  // Let's use mScriptGlobalObject. Even if the document is already removed from
  // the docshell, the outer window might be still obtainable from the it.
  nsCOMPtr<nsPIDOMWindow> win;
  if (mRemovedFromDocShell) {
    nsCOMPtr<nsIInterfaceRequestor> requestor =
      do_QueryReferent(mDocumentContainer);
    if (requestor) {
      // The docshell returns the outer window we are done.
      win = do_GetInterface(requestor);
    }
  } else {
    win = do_QueryInterface(mScriptGlobalObject);
    if (win) {
      // mScriptGlobalObject is always the inner window, let's get the outer.
      win = win->GetOuterWindow();
    }
  }

  return win;
}

nsScriptLoader*
nsDocument::ScriptLoader()
{
  return mScriptLoader;
}

bool
nsDocument::InternalAllowXULXBL()
{
  if (nsContentUtils::AllowXULXBLForPrincipal(NodePrincipal())) {
    mAllowXULXBL = eTriTrue;
    return true;
  }

  mAllowXULXBL = eTriFalse;
  return false;
}

// Note: We don't hold a reference to the document observer; we assume
// that it has a live reference to the document.
void
nsDocument::AddObserver(nsIDocumentObserver* aObserver)
{
  NS_ASSERTION(mObservers.IndexOf(aObserver) == nsTArray<int>::NoIndex,
               "Observer already in the list");
  mObservers.AppendElement(aObserver);
  AddMutationObserver(aObserver);
}

bool
nsDocument::RemoveObserver(nsIDocumentObserver* aObserver)
{
  // If we're in the process of destroying the document (and we're
  // informing the observers of the destruction), don't remove the
  // observers from the list. This is not a big deal, since we
  // don't hold a live reference to the observers.
  if (!mInDestructor) {
    RemoveMutationObserver(aObserver);
    return mObservers.RemoveElement(aObserver);
  }

  return mObservers.Contains(aObserver);
}

void
nsDocument::MaybeEndOutermostXBLUpdate()
{
  // Only call BindingManager()->EndOutermostUpdate() when
  // we're not in an update and it is safe to run scripts.
  if (mUpdateNestLevel == 0 && mInXBLUpdate) {
    if (nsContentUtils::IsSafeToRunScript()) {
      mInXBLUpdate = false;
      BindingManager()->EndOutermostUpdate();
    } else if (!mInDestructor) {
      nsContentUtils::AddScriptRunner(
        NS_NewRunnableMethod(this, &nsDocument::MaybeEndOutermostXBLUpdate));
    }
  }
}

void
nsDocument::BeginUpdate(nsUpdateType aUpdateType)
{
  if (mUpdateNestLevel == 0 && !mInXBLUpdate) {
    mInXBLUpdate = true;
    BindingManager()->BeginOutermostUpdate();
  }

  ++mUpdateNestLevel;
  nsContentUtils::AddScriptBlocker();
  NS_DOCUMENT_NOTIFY_OBSERVERS(BeginUpdate, (this, aUpdateType));
}

void
nsDocument::EndUpdate(nsUpdateType aUpdateType)
{
  NS_DOCUMENT_NOTIFY_OBSERVERS(EndUpdate, (this, aUpdateType));

  nsContentUtils::RemoveScriptBlocker();

  --mUpdateNestLevel;

  // This set of updates may have created XBL bindings.  Let the
  // binding manager know we're done.
  MaybeEndOutermostXBLUpdate();

  MaybeInitializeFinalizeFrameLoaders();
}

void
nsDocument::BeginLoad()
{
  // Block onload here to prevent having to deal with blocking and
  // unblocking it while we know the document is loading.
  BlockOnload();

  if (mScriptLoader) {
    mScriptLoader->BeginDeferringScripts();
  }

  NS_DOCUMENT_NOTIFY_OBSERVERS(BeginLoad, (this));
}

void
nsDocument::ReportEmptyGetElementByIdArg()
{
  nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,
                                  "DOM", this,
                                  nsContentUtils::eDOM_PROPERTIES,
                                  "EmptyGetElementByIdParam");
}

Element*
nsDocument::GetElementById(const nsAString& aElementId)
{
  if (!CheckGetElementByIdArg(aElementId)) {
    return nullptr;
  }

  nsIdentifierMapEntry *entry = mIdentifierMap.GetEntry(aElementId);
  return entry ? entry->GetIdElement() : nullptr;
}

const nsSmallVoidArray*
nsDocument::GetAllElementsForId(const nsAString& aElementId) const
{
  if (aElementId.IsEmpty()) {
    return nullptr;
  }

  nsIdentifierMapEntry *entry = mIdentifierMap.GetEntry(aElementId);
  return entry ? entry->GetIdElements() : nullptr;
}

NS_IMETHODIMP
nsDocument::GetElementById(const nsAString& aId, nsIDOMElement** aReturn)
{
  Element *content = GetElementById(aId);
  if (content) {
    return CallQueryInterface(content, aReturn);
  }

  *aReturn = nullptr;

  return NS_OK;
}

Element*
nsDocument::AddIDTargetObserver(nsIAtom* aID, IDTargetObserver aObserver,
                                void* aData, bool aForImage)
{
  nsDependentAtomString id(aID);

  if (!CheckGetElementByIdArg(id))
    return nullptr;

  nsIdentifierMapEntry *entry = mIdentifierMap.PutEntry(id);
  NS_ENSURE_TRUE(entry, nullptr);

  entry->AddContentChangeCallback(aObserver, aData, aForImage);
  return aForImage ? entry->GetImageIdElement() : entry->GetIdElement();
}

void
nsDocument::RemoveIDTargetObserver(nsIAtom* aID, IDTargetObserver aObserver,
                                   void* aData, bool aForImage)
{
  nsDependentAtomString id(aID);

  if (!CheckGetElementByIdArg(id))
    return;

  nsIdentifierMapEntry *entry = mIdentifierMap.GetEntry(id);
  if (!entry) {
    return;
  }

  entry->RemoveContentChangeCallback(aObserver, aData, aForImage);
}

NS_IMETHODIMP
nsDocument::MozSetImageElement(const nsAString& aImageElementId,
                               nsIDOMElement* aImageElement)
{
  nsCOMPtr<Element> el = do_QueryInterface(aImageElement);
  MozSetImageElement(aImageElementId, el);
  return NS_OK;
}

void
nsDocument::MozSetImageElement(const nsAString& aImageElementId,
                               Element* aElement)
{
  if (aImageElementId.IsEmpty())
    return;

  // Hold a script blocker while calling SetImageElement since that can call
  // out to id-observers
  nsAutoScriptBlocker scriptBlocker;

  nsIdentifierMapEntry *entry = mIdentifierMap.PutEntry(aImageElementId);
  if (entry) {
    entry->SetImageElement(aElement);
    if (entry->IsEmpty()) {
      mIdentifierMap.RemoveEntry(aImageElementId);
    }
  }
}

Element*
nsDocument::LookupImageElement(const nsAString& aId)
{
  if (aId.IsEmpty())
    return nullptr;

  nsIdentifierMapEntry *entry = mIdentifierMap.GetEntry(aId);
  return entry ? entry->GetImageIdElement() : nullptr;
}

void
nsDocument::DispatchContentLoadedEvents()
{
  // If you add early returns from this method, make sure you're
  // calling UnblockOnload properly.

  // Unpin references to preloaded images
  mPreloadingImages.Clear();

  if (mTiming) {
    mTiming->NotifyDOMContentLoadedStart(nsIDocument::GetDocumentURI());
  }

  // Fire a DOM event notifying listeners that this document has been
  // loaded (excluding images and other loads initiated by this
  // document).
  nsContentUtils::DispatchTrustedEvent(this, static_cast<nsIDocument*>(this),
                                       NS_LITERAL_STRING("DOMContentLoaded"),
                                       true, true);

  if (mTiming) {
    mTiming->NotifyDOMContentLoadedEnd(nsIDocument::GetDocumentURI());
  }

  // If this document is a [i]frame, fire a DOMFrameContentLoaded
  // event on all parent documents notifying that the HTML (excluding
  // other external files such as images and stylesheets) in a frame
  // has finished loading.

  // target_frame is the [i]frame element that will be used as the
  // target for the event. It's the [i]frame whose content is done
  // loading.
  nsCOMPtr<EventTarget> target_frame;

  if (mParentDocument) {
    target_frame = mParentDocument->FindContentForSubDocument(this);
  }

  if (target_frame) {
    nsCOMPtr<nsIDocument> parent = mParentDocument;
    do {
      nsCOMPtr<nsIDOMDocument> domDoc = do_QueryInterface(parent);

      nsCOMPtr<nsIDOMEvent> event;
      if (domDoc) {
        domDoc->CreateEvent(NS_LITERAL_STRING("Events"),
                            getter_AddRefs(event));

      }

      if (event) {
        event->InitEvent(NS_LITERAL_STRING("DOMFrameContentLoaded"), true,
                         true);

        event->SetTarget(target_frame);
        event->SetTrusted(true);

        // To dispatch this event we must manually call
        // nsEventDispatcher::Dispatch() on the ancestor document since the
        // target is not in the same document, so the event would never reach
        // the ancestor document if we used the normal event
        // dispatching code.

        nsEvent* innerEvent = event->GetInternalNSEvent();
        if (innerEvent) {
          nsEventStatus status = nsEventStatus_eIgnore;

          nsIPresShell *shell = parent->GetShell();
          if (shell) {
            nsRefPtr<nsPresContext> context = shell->GetPresContext();

            if (context) {
              nsEventDispatcher::Dispatch(parent, context, innerEvent, event,
                                          &status);
            }
          }
        }
      }

      parent = parent->GetParentDocument();
    } while (parent);
  }

  // If the document has a manifest attribute, fire a MozApplicationManifest
  // event.
  Element* root = GetRootElement();
  if (root && root->HasAttr(kNameSpaceID_None, nsGkAtoms::manifest)) {
    nsContentUtils::DispatchChromeEvent(this, static_cast<nsIDocument*>(this),
                                        NS_LITERAL_STRING("MozApplicationManifest"),
                                        true, true);
  }

  UnblockOnload(true);
}

void
nsDocument::EndLoad()
{
  // Drop the ref to our parser, if any, but keep hold of the sink so that we
  // can flush it from FlushPendingNotifications as needed.  We might have to
  // do that to get a StartLayout() to happen.
  if (mParser) {
    mWeakSink = do_GetWeakReference(mParser->GetContentSink());
    mParser = nullptr;
  }

  NS_DOCUMENT_NOTIFY_OBSERVERS(EndLoad, (this));

  if (!mSynchronousDOMContentLoaded) {
    nsRefPtr<nsIRunnable> ev =
      NS_NewRunnableMethod(this, &nsDocument::DispatchContentLoadedEvents);
    NS_DispatchToCurrentThread(ev);
  } else {
    DispatchContentLoadedEvents();
  }
}

void
nsDocument::ContentStateChanged(nsIContent* aContent, nsEventStates aStateMask)
{
  NS_PRECONDITION(!nsContentUtils::IsSafeToRunScript(),
                  "Someone forgot a scriptblocker");
  NS_DOCUMENT_NOTIFY_OBSERVERS(ContentStateChanged,
                               (this, aContent, aStateMask));
}

void
nsDocument::DocumentStatesChanged(nsEventStates aStateMask)
{
  // Invalidate our cached state.
  mGotDocumentState &= ~aStateMask;
  mDocumentState &= ~aStateMask;

  NS_DOCUMENT_NOTIFY_OBSERVERS(DocumentStatesChanged, (this, aStateMask));
}

void
nsDocument::StyleRuleChanged(nsIStyleSheet* aSheet,
                             nsIStyleRule* aOldStyleRule,
                             nsIStyleRule* aNewStyleRule)
{
  NS_DOCUMENT_NOTIFY_OBSERVERS(StyleRuleChanged,
                               (this, aSheet,
                                aOldStyleRule, aNewStyleRule));

  if (StyleSheetChangeEventsEnabled()) {
    nsCOMPtr<css::Rule> rule = do_QueryInterface(aNewStyleRule);
    DO_STYLESHEET_NOTIFICATION(NS_NewDOMStyleRuleChangeEvent,
                               nsIDOMStyleRuleChangeEvent,
                               InitStyleRuleChangeEvent,
                               "StyleRuleChanged",
                               rule ? rule->GetDOMRule() : nullptr);
  }
}

void
nsDocument::StyleRuleAdded(nsIStyleSheet* aSheet,
                           nsIStyleRule* aStyleRule)
{
  NS_DOCUMENT_NOTIFY_OBSERVERS(StyleRuleAdded,
                               (this, aSheet, aStyleRule));

  if (StyleSheetChangeEventsEnabled()) {
    nsCOMPtr<css::Rule> rule = do_QueryInterface(aStyleRule);
    DO_STYLESHEET_NOTIFICATION(NS_NewDOMStyleRuleChangeEvent,
                               nsIDOMStyleRuleChangeEvent,
                               InitStyleRuleChangeEvent,
                               "StyleRuleAdded",
                               rule ? rule->GetDOMRule() : nullptr);
  }
}

void
nsDocument::StyleRuleRemoved(nsIStyleSheet* aSheet,
                             nsIStyleRule* aStyleRule)
{
  NS_DOCUMENT_NOTIFY_OBSERVERS(StyleRuleRemoved,
                               (this, aSheet, aStyleRule));

  if (StyleSheetChangeEventsEnabled()) {
    nsCOMPtr<css::Rule> rule = do_QueryInterface(aStyleRule);
    DO_STYLESHEET_NOTIFICATION(NS_NewDOMStyleRuleChangeEvent,
                               nsIDOMStyleRuleChangeEvent,
                               InitStyleRuleChangeEvent,
                               "StyleRuleRemoved",
                               rule ? rule->GetDOMRule() : nullptr);
  }
}

#undef DO_STYLESHEET_NOTIFICATION


//
// nsIDOMDocument interface
//
DocumentType*
nsIDocument::GetDoctype() const
{
  for (nsIContent* child = GetFirstChild();
       child;
       child = child->GetNextSibling()) {
    if (child->NodeType() == nsIDOMNode::DOCUMENT_TYPE_NODE) {
      return static_cast<DocumentType*>(child);
    }
  }
  return nullptr;
}

NS_IMETHODIMP
nsDocument::GetDoctype(nsIDOMDocumentType** aDoctype)
{
  MOZ_ASSERT(aDoctype);
  nsCOMPtr<nsIDOMDocumentType> doctype = nsIDocument::GetDoctype();
  doctype.forget(aDoctype);
  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetImplementation(nsIDOMDOMImplementation** aImplementation)
{
  ErrorResult rv;
  *aImplementation = GetImplementation(rv);
  if (rv.Failed()) {
    MOZ_ASSERT(!*aImplementation);
    return rv.ErrorCode();
  }
  NS_ADDREF(*aImplementation);
  return NS_OK;
}

DOMImplementation*
nsDocument::GetImplementation(ErrorResult& rv)
{
  if (!mDOMImplementation) {
    nsCOMPtr<nsIURI> uri;
    NS_NewURI(getter_AddRefs(uri), "about:blank");
    if (!uri) {
      rv.Throw(NS_ERROR_OUT_OF_MEMORY);
      return nullptr;
    }
    bool hasHadScriptObject = true;
    nsIScriptGlobalObject* scriptObject =
      GetScriptHandlingObject(hasHadScriptObject);
    if (!scriptObject && hasHadScriptObject) {
      rv.Throw(NS_ERROR_UNEXPECTED);
      return nullptr;
    }
    mDOMImplementation = new DOMImplementation(this,
      scriptObject ? scriptObject : GetScopeObject(), uri, uri);
  }

  return mDOMImplementation;
}

NS_IMETHODIMP
nsDocument::GetDocumentElement(nsIDOMElement** aDocumentElement)
{
  NS_ENSURE_ARG_POINTER(aDocumentElement);

  Element* root = GetRootElement();
  if (root) {
    return CallQueryInterface(root, aDocumentElement);
  }

  *aDocumentElement = nullptr;

  return NS_OK;
}

NS_IMETHODIMP
nsDocument::CreateElement(const nsAString& aTagName,
                          nsIDOMElement** aReturn)
{
  *aReturn = nullptr;
  ErrorResult rv;
  nsCOMPtr<Element> element = nsIDocument::CreateElement(aTagName, rv);
  NS_ENSURE_FALSE(rv.Failed(), rv.ErrorCode());
  return CallQueryInterface(element, aReturn);
}

bool IsLowercaseASCII(const nsAString& aValue)
{
  int32_t len = aValue.Length();
  for (int32_t i = 0; i < len; ++i) {
    PRUnichar c = aValue[i];
    if (!(0x0061 <= (c) && ((c) <= 0x007a))) {
      return false;
    }
  }
  return true;
}

already_AddRefed<Element>
nsIDocument::CreateElement(const nsAString& aTagName, ErrorResult& rv)
{
  rv = nsContentUtils::CheckQName(aTagName, false);
  if (rv.Failed()) {
    return nullptr;
  }

  bool needsLowercase = IsHTML() && !IsLowercaseASCII(aTagName);
  nsAutoString lcTagName;
  if (needsLowercase) {
    nsContentUtils::ASCIIToLower(aTagName, lcTagName);
  }

  nsCOMPtr<nsIContent> content;
  rv = CreateElem(needsLowercase ? lcTagName : aTagName,
                  nullptr, mDefaultElementType, getter_AddRefs(content));
  if (rv.Failed()) {
    return nullptr;
  }
  return dont_AddRef(content.forget().get()->AsElement());
}

NS_IMETHODIMP
nsDocument::CreateElementNS(const nsAString& aNamespaceURI,
                            const nsAString& aQualifiedName,
                            nsIDOMElement** aReturn)
{
  *aReturn = nullptr;
  ErrorResult rv;
  nsCOMPtr<Element> element =
    nsIDocument::CreateElementNS(aNamespaceURI, aQualifiedName, rv);
  NS_ENSURE_FALSE(rv.Failed(), rv.ErrorCode());
  return CallQueryInterface(element, aReturn);
}

already_AddRefed<Element>
nsIDocument::CreateElementNS(const nsAString& aNamespaceURI,
                             const nsAString& aQualifiedName,
                             ErrorResult& rv)
{
  nsCOMPtr<nsINodeInfo> nodeInfo;
  rv = nsContentUtils::GetNodeInfoFromQName(aNamespaceURI,
                                            aQualifiedName,
                                            mNodeInfoManager,
                                            nsIDOMNode::ELEMENT_NODE,
                                            getter_AddRefs(nodeInfo));
  if (rv.Failed()) {
    return nullptr;
  }

  nsCOMPtr<nsIContent> content;
  rv = NS_NewElement(getter_AddRefs(content), nodeInfo.forget(),
                     NOT_FROM_PARSER);
  if (rv.Failed()) {
    return nullptr;
  }
  return dont_AddRef(content.forget().get()->AsElement());
}

NS_IMETHODIMP
nsDocument::CreateTextNode(const nsAString& aData, nsIDOMText** aReturn)
{
  *aReturn = nsIDocument::CreateTextNode(aData).get();
  return NS_OK;
}

already_AddRefed<nsTextNode>
nsIDocument::CreateTextNode(const nsAString& aData) const
{
  nsRefPtr<nsTextNode> text = new nsTextNode(mNodeInfoManager);
  // Don't notify; this node is still being created.
  text->SetText(aData, false);
  return text.forget();
}

NS_IMETHODIMP
nsDocument::CreateDocumentFragment(nsIDOMDocumentFragment** aReturn)
{
  *aReturn = nsIDocument::CreateDocumentFragment().get();
  return NS_OK;
}

already_AddRefed<DocumentFragment>
nsIDocument::CreateDocumentFragment() const
{
  nsRefPtr<DocumentFragment> frag = new DocumentFragment(mNodeInfoManager);
  return frag.forget();
}

NS_IMETHODIMP
nsDocument::CreateComment(const nsAString& aData, nsIDOMComment** aReturn)
{
  *aReturn = nsIDocument::CreateComment(aData).get();
  return NS_OK;
}

// Unfortunately, bareword "Comment" is ambiguous with some Mac system headers.
already_AddRefed<dom::Comment>
nsIDocument::CreateComment(const nsAString& aData) const
{
  nsRefPtr<dom::Comment> comment = new dom::Comment(mNodeInfoManager);

  // Don't notify; this node is still being created.
  comment->SetText(aData, false);
  return comment.forget();
}

NS_IMETHODIMP
nsDocument::CreateCDATASection(const nsAString& aData,
                               nsIDOMCDATASection** aReturn)
{
  NS_ENSURE_ARG_POINTER(aReturn);
  ErrorResult rv;
  *aReturn = nsIDocument::CreateCDATASection(aData, rv).get();
  return rv.ErrorCode();
}

already_AddRefed<CDATASection>
nsIDocument::CreateCDATASection(const nsAString& aData,
                                ErrorResult& rv)
{
  if (IsHTML()) {
    rv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
    return nullptr;
  }

  if (FindInReadable(NS_LITERAL_STRING("]]>"), aData)) {
    rv.Throw(NS_ERROR_DOM_INVALID_CHARACTER_ERR);
    return nullptr;
  }

  nsRefPtr<CDATASection> cdata = new CDATASection(mNodeInfoManager);

  // Don't notify; this node is still being created.
  cdata->SetText(aData, false);

  return cdata.forget();
}

NS_IMETHODIMP
nsDocument::CreateProcessingInstruction(const nsAString& aTarget,
                                        const nsAString& aData,
                                        nsIDOMProcessingInstruction** aReturn)
{
  ErrorResult rv;
  *aReturn = nsIDocument::CreateProcessingInstruction(aTarget, aData, rv).get();
  return rv.ErrorCode();
}

already_AddRefed<ProcessingInstruction>
nsIDocument::CreateProcessingInstruction(const nsAString& aTarget,
                                         const nsAString& aData,
                                         ErrorResult& rv) const
{
  nsresult res = nsContentUtils::CheckQName(aTarget, false);
  if (NS_FAILED(res)) {
    rv.Throw(res);
    return nullptr;
  }

  if (FindInReadable(NS_LITERAL_STRING("?>"), aData)) {
    rv.Throw(NS_ERROR_DOM_INVALID_CHARACTER_ERR);
    return nullptr;
  }

  nsRefPtr<ProcessingInstruction> pi =
    NS_NewXMLProcessingInstruction(mNodeInfoManager, aTarget, aData);

  return pi.forget();
}

NS_IMETHODIMP
nsDocument::CreateAttribute(const nsAString& aName,
                            nsIDOMAttr** aReturn)
{
  ErrorResult rv;
  *aReturn = nsIDocument::CreateAttribute(aName, rv).get();
  return rv.ErrorCode();
}

already_AddRefed<Attr>
nsIDocument::CreateAttribute(const nsAString& aName, ErrorResult& rv)
{
  WarnOnceAbout(eCreateAttribute);

  if (!mNodeInfoManager) {
    rv.Throw(NS_ERROR_NOT_INITIALIZED);
    return nullptr;
  }

  nsresult res = nsContentUtils::CheckQName(aName, false);
  if (NS_FAILED(res)) {
    rv.Throw(res);
    return nullptr;
  }

  nsCOMPtr<nsINodeInfo> nodeInfo;
  res = mNodeInfoManager->GetNodeInfo(aName, nullptr, kNameSpaceID_None,
                                      nsIDOMNode::ATTRIBUTE_NODE,
                                      getter_AddRefs(nodeInfo));
  if (NS_FAILED(res)) {
    rv.Throw(res);
    return nullptr;
  }

  nsRefPtr<Attr> attribute = new Attr(nullptr, nodeInfo.forget(),
                                      EmptyString(), false);
  return attribute.forget();
}

NS_IMETHODIMP
nsDocument::CreateAttributeNS(const nsAString & aNamespaceURI,
                              const nsAString & aQualifiedName,
                              nsIDOMAttr **aResult)
{
  ErrorResult rv;
  *aResult =
    nsIDocument::CreateAttributeNS(aNamespaceURI, aQualifiedName, rv).get();
  return rv.ErrorCode();
}

already_AddRefed<Attr>
nsIDocument::CreateAttributeNS(const nsAString& aNamespaceURI,
                               const nsAString& aQualifiedName,
                               ErrorResult& rv)
{
  WarnOnceAbout(eCreateAttributeNS);

  nsCOMPtr<nsINodeInfo> nodeInfo;
  rv = nsContentUtils::GetNodeInfoFromQName(aNamespaceURI,
                                            aQualifiedName,
                                            mNodeInfoManager,
                                            nsIDOMNode::ATTRIBUTE_NODE,
                                            getter_AddRefs(nodeInfo));
  if (rv.Failed()) {
    return nullptr;
  }

  nsRefPtr<Attr> attribute = new Attr(nullptr, nodeInfo.forget(),
                                      EmptyString(), true);
  return attribute.forget();
}

static JSBool
CustomElementConstructor(JSContext *aCx, unsigned aArgc, JS::Value* aVp)
{
  JS::CallArgs args = JS::CallArgsFromVp(aArgc, aVp);

  JS::Rooted<JSObject*> global(aCx,
    JS_GetGlobalForObject(aCx, &args.callee()));
  nsCOMPtr<nsPIDOMWindow> window = do_QueryWrapper(aCx, global);
  MOZ_ASSERT(window, "Should have a non-null window");

  nsIDocument* document = window->GetDoc();

  // Function name is the type of the custom element.
  JSString* jsFunName =
    JS_GetFunctionId(JS_ValueToFunction(aCx, args.calleev()));
  nsDependentJSString elemName;
  if (!elemName.init(aCx, jsFunName)) {
    return false;
  }

  nsCOMPtr<nsIContent> newElement;
  nsresult rv = document->CreateElem(elemName, nullptr, kNameSpaceID_XHTML,
                                     getter_AddRefs(newElement));
  rv = nsContentUtils::WrapNative(aCx, global, newElement, newElement,
                                  args.rval().address());
  NS_ENSURE_SUCCESS(rv, false);

  return true;
}

bool
nsDocument::RegisterEnabled()
{
  static bool sPrefValue =
    Preferences::GetBool("dom.webcomponents.enabled", false);
  return sPrefValue;
}

JSObject*
nsDocument::Register(JSContext* aCx, const nsAString& aName,
                     const ElementRegistrationOptions& aOptions,
                     ErrorResult& rv)
{
  nsAutoString lcName;
  nsContentUtils::ASCIIToLower(aName, lcName);
  if (!StringBeginsWith(lcName, NS_LITERAL_STRING("x-"))) {
    rv.Throw(NS_ERROR_DOM_INVALID_CHARACTER_ERR);
    return nullptr;
  }
  if (NS_FAILED(nsContentUtils::CheckQName(lcName, false))) {
    rv.Throw(NS_ERROR_DOM_INVALID_CHARACTER_ERR);
    return nullptr;
  }

  nsIGlobalObject* sgo = GetScopeObject();
  if (!sgo) {
    rv.Throw(NS_ERROR_UNEXPECTED);
    return nullptr;
  }
  JS::Rooted<JSObject*> global(aCx, sgo->GetGlobalJSObject());

  JSAutoCompartment ac(aCx, global);

  JS::Handle<JSObject*> htmlProto(
    HTMLElementBinding::GetProtoObject(aCx, global));
  if (!htmlProto) {
    rv.Throw(NS_ERROR_OUT_OF_MEMORY);
    return nullptr;
  }

  JS::Rooted<JSObject*> protoObject(aCx);
  if (!aOptions.mPrototype) {
    protoObject = JS_NewObject(aCx, nullptr, htmlProto, nullptr);
    if (!protoObject) {
      rv.Throw(NS_ERROR_UNEXPECTED);
      return nullptr;
    }
  } else {
    // If a prototype is provided, we must check to ensure that it inherits
    // from HTMLElement.
    protoObject = aOptions.mPrototype;
    if (!JS_WrapObject(aCx, protoObject.address())) {
      rv.Throw(NS_ERROR_UNEXPECTED);
      return nullptr;
    }

    // Check the proto chain for HTMLElement prototype.
    JS::Rooted<JSObject*> protoProto(aCx);
    if (!JS_GetPrototype(aCx, protoObject, protoProto.address())) {
      rv.Throw(NS_ERROR_UNEXPECTED);
      return nullptr;
    }
    while (protoProto) {
      if (protoProto == htmlProto) {
        break;
      }
      if (!JS_GetPrototype(aCx, protoProto, protoProto.address())) {
        rv.Throw(NS_ERROR_UNEXPECTED);
        return nullptr;
      }
    }

    if (!protoProto) {
      rv.Throw(NS_ERROR_DOM_TYPE_MISMATCH_ERR);
      return nullptr;
    }
  }

  // Associate the prototype with the custom element.
  mCustomPrototypes.Put(lcName, protoObject);

  // Do element upgrade.
  nsRefPtr<nsContentList> list = GetElementsByTagName(lcName);
  for (uint32_t i = 0; i < list->Length(false); i++) {
    nsCOMPtr<nsINode> oldNode = list->Item(i, false);

    // TODO(wchen): Perform upgrade on Shadow DOM when implemented.
    // Bug 806506.
    nsCOMPtr<nsINode> newNode;
    rv = nsNodeUtils::Clone(oldNode, true, getter_AddRefs(newNode));
    if (rv.Failed()) {
      return nullptr;
    }

    nsINode* parentNode = oldNode->GetParentNode();
    MOZ_ASSERT(parentNode, "Node obtained by GetElementsByTagName.");
    nsCOMPtr<Element> newElement = do_QueryInterface(newNode);
    MOZ_ASSERT(newElement, "Cloned of node obtained by GetElementsByTagName.");

    parentNode->ReplaceChild(*newNode, *oldNode, rv);
    if (rv.Failed()) {
      return nullptr;
    }

    // Dispatch elementreplaced to replaced elements.
    nsCOMPtr<nsIDOMEvent> event;
    rv = CreateEvent(NS_LITERAL_STRING("elementreplace"), getter_AddRefs(event));
    if (rv.Failed()) {
      return nullptr;
    }

    if (aOptions.mLifecycle.mCreated) {
      // Don't abort the upgrade algorithm if the callback throws an
      // exception.
      ErrorResult dummy;
      aOptions.mLifecycle.mCreated->Call(newElement, dummy);
    }

    nsCOMPtr<nsIDOMElementReplaceEvent> ptEvent = do_QueryInterface(event);
    MOZ_ASSERT(ptEvent);

    nsCOMPtr<nsIDOMElement> element = do_QueryInterface(newElement);
    rv = ptEvent->InitElementReplaceEvent(NS_LITERAL_STRING("elementreplace"),
                                          false, false, element);
    if (rv.Failed()) {
      return nullptr;
    }

    event->SetTrusted(true);
    event->SetTarget(oldNode);
    nsEventDispatcher::DispatchDOMEvent(oldNode, nullptr, event,
                                        nullptr, nullptr);
  }

  nsContentUtils::DispatchTrustedEvent(this, static_cast<nsIDocument*>(this),
                                       NS_LITERAL_STRING("elementupgrade"),
                                       true, true);

  // Create constructor to return. Store the name of the custom element as the
  // name of the function.
  JSFunction* constructor = JS_NewFunction(aCx, CustomElementConstructor, 0,
                                           JSFUN_CONSTRUCTOR, nullptr,
                                           NS_ConvertUTF16toUTF8(lcName).get());
  JSObject* constructorObject = JS_GetFunctionObject(constructor);
  return constructorObject;
}

NS_IMETHODIMP
nsDocument::GetElementsByTagName(const nsAString& aTagname,
                                 nsIDOMNodeList** aReturn)
{
  nsRefPtr<nsContentList> list = GetElementsByTagName(aTagname);
  NS_ENSURE_TRUE(list, NS_ERROR_OUT_OF_MEMORY);

  // transfer ref to aReturn
  *aReturn = list.forget().get();
  return NS_OK;
}

already_AddRefed<nsContentList>
nsIDocument::GetElementsByTagNameNS(const nsAString& aNamespaceURI,
                                    const nsAString& aLocalName)
{
  int32_t nameSpaceId = kNameSpaceID_Wildcard;

  if (!aNamespaceURI.EqualsLiteral("*")) {
    nsresult rv =
      nsContentUtils::NameSpaceManager()->RegisterNameSpace(aNamespaceURI,
                                                            nameSpaceId);
    NS_ENSURE_SUCCESS(rv, nullptr);
  }

  NS_ASSERTION(nameSpaceId != kNameSpaceID_Unknown, "Unexpected namespace ID!");

  return NS_GetContentList(this, nameSpaceId, aLocalName);
}

NS_IMETHODIMP
nsDocument::GetElementsByTagNameNS(const nsAString& aNamespaceURI,
                                   const nsAString& aLocalName,
                                   nsIDOMNodeList** aReturn)
{
  nsRefPtr<nsContentList> list =
    nsIDocument::GetElementsByTagNameNS(aNamespaceURI, aLocalName);
  NS_ENSURE_TRUE(list, NS_ERROR_OUT_OF_MEMORY);

  // transfer ref to aReturn
  *aReturn = list.forget().get();
  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetAsync(bool *aAsync)
{
  NS_ERROR("nsDocument::GetAsync() should be overriden by subclass!");

  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
nsDocument::SetAsync(bool aAsync)
{
  NS_ERROR("nsDocument::SetAsync() should be overriden by subclass!");

  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
nsDocument::Load(const nsAString& aUrl, bool *aReturn)
{
  NS_ERROR("nsDocument::Load() should be overriden by subclass!");

  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
nsDocument::GetStyleSheets(nsIDOMStyleSheetList** aStyleSheets)
{
  NS_ADDREF(*aStyleSheets = StyleSheets());
  return NS_OK;
}

nsIDOMStyleSheetList*
nsDocument::StyleSheets()
{
  if (!mDOMStyleSheets) {
    mDOMStyleSheets = new nsDOMStyleSheetList(this);
  }
  return mDOMStyleSheets;
}

NS_IMETHODIMP
nsDocument::GetMozSelectedStyleSheetSet(nsAString& aSheetSet)
{
  nsIDocument::GetSelectedStyleSheetSet(aSheetSet);
  return NS_OK;
}

void
nsIDocument::GetSelectedStyleSheetSet(nsAString& aSheetSet)
{
  aSheetSet.Truncate();

  // Look through our sheets, find the selected set title
  int32_t count = GetNumberOfStyleSheets();
  nsAutoString title;
  for (int32_t index = 0; index < count; index++) {
    nsIStyleSheet* sheet = GetStyleSheetAt(index);
    NS_ASSERTION(sheet, "Null sheet in sheet list!");

    nsCOMPtr<nsIDOMStyleSheet> domSheet = do_QueryInterface(sheet);
    NS_ASSERTION(domSheet, "Sheet must QI to nsIDOMStyleSheet");
    bool disabled;
    domSheet->GetDisabled(&disabled);
    if (disabled) {
      // Disabled sheets don't affect the currently selected set
      continue;
    }

    sheet->GetTitle(title);

    if (aSheetSet.IsEmpty()) {
      aSheetSet = title;
    } else if (!title.IsEmpty() && !aSheetSet.Equals(title)) {
      // Sheets from multiple sets enabled; return null string, per spec.
      SetDOMStringToNull(aSheetSet);
      return;
    }
  }
}

NS_IMETHODIMP
nsDocument::SetMozSelectedStyleSheetSet(const nsAString& aSheetSet)
{
  SetSelectedStyleSheetSet(aSheetSet);
  return NS_OK;
}

void
nsDocument::SetSelectedStyleSheetSet(const nsAString& aSheetSet)
{
  if (DOMStringIsNull(aSheetSet)) {
    return;
  }

  // Must update mLastStyleSheetSet before doing anything else with stylesheets
  // or CSSLoaders.
  mLastStyleSheetSet = aSheetSet;
  EnableStyleSheetsForSetInternal(aSheetSet, true);
}

NS_IMETHODIMP
nsDocument::GetLastStyleSheetSet(nsAString& aSheetSet)
{
  nsString sheetSet;
  GetLastStyleSheetSet(sheetSet);
  aSheetSet = sheetSet;
  return NS_OK;
}

void
nsDocument::GetLastStyleSheetSet(nsString& aSheetSet)
{
  aSheetSet = mLastStyleSheetSet;
}

NS_IMETHODIMP
nsDocument::GetPreferredStyleSheetSet(nsAString& aSheetSet)
{
  nsIDocument::GetPreferredStyleSheetSet(aSheetSet);
  return NS_OK;
}

void
nsIDocument::GetPreferredStyleSheetSet(nsAString& aSheetSet)
{
  GetHeaderData(nsGkAtoms::headerDefaultStyle, aSheetSet);
}

NS_IMETHODIMP
nsDocument::GetStyleSheetSets(nsIDOMDOMStringList** aList)
{
  NS_ADDREF(*aList = StyleSheetSets());
  return NS_OK;
}

nsIDOMDOMStringList*
nsDocument::StyleSheetSets()
{
  if (!mStyleSheetSetList) {
    mStyleSheetSetList = new nsDOMStyleSheetSetList(this);
  }
  return mStyleSheetSetList;
}

NS_IMETHODIMP
nsDocument::MozEnableStyleSheetsForSet(const nsAString& aSheetSet)
{
  EnableStyleSheetsForSet(aSheetSet);
  return NS_OK;
}

void
nsDocument::EnableStyleSheetsForSet(const nsAString& aSheetSet)
{
  // Per spec, passing in null is a no-op.
  if (!DOMStringIsNull(aSheetSet)) {
    // Note: must make sure to not change the CSSLoader's preferred sheet --
    // that value should be equal to either our lastStyleSheetSet (if that's
    // non-null) or to our preferredStyleSheetSet.  And this method doesn't
    // change either of those.
    EnableStyleSheetsForSetInternal(aSheetSet, false);
  }
}

void
nsDocument::EnableStyleSheetsForSetInternal(const nsAString& aSheetSet,
                                            bool aUpdateCSSLoader)
{
  BeginUpdate(UPDATE_STYLE);
  int32_t count = GetNumberOfStyleSheets();
  nsAutoString title;
  for (int32_t index = 0; index < count; index++) {
    nsIStyleSheet* sheet = GetStyleSheetAt(index);
    NS_ASSERTION(sheet, "Null sheet in sheet list!");
    sheet->GetTitle(title);
    if (!title.IsEmpty()) {
      sheet->SetEnabled(title.Equals(aSheetSet));
    }
  }
  if (aUpdateCSSLoader) {
    CSSLoader()->SetPreferredSheet(aSheetSet);
  }
  EndUpdate(UPDATE_STYLE);
}

NS_IMETHODIMP
nsDocument::GetCharacterSet(nsAString& aCharacterSet)
{
  nsIDocument::GetCharacterSet(aCharacterSet);
  return NS_OK;
}

void
nsIDocument::GetCharacterSet(nsAString& aCharacterSet) const
{
  CopyASCIItoUTF16(GetDocumentCharacterSet(), aCharacterSet);
}

NS_IMETHODIMP
nsDocument::ImportNode(nsIDOMNode* aImportedNode,
                       bool aDeep,
                       uint8_t aArgc,
                       nsIDOMNode** aResult)
{
  if (aArgc == 0) {
    aDeep = true;
  }

  *aResult = nullptr;

  nsCOMPtr<nsINode> imported = do_QueryInterface(aImportedNode);
  NS_ENSURE_TRUE(imported, NS_ERROR_UNEXPECTED);

  ErrorResult rv;
  nsCOMPtr<nsINode> result = nsIDocument::ImportNode(*imported, aDeep, rv);
  if (rv.Failed()) {
    return rv.ErrorCode();
  }

  NS_ADDREF(*aResult = result->AsDOMNode());
  return NS_OK;
}

already_AddRefed<nsINode>
nsIDocument::ImportNode(nsINode& aNode, bool aDeep, ErrorResult& rv) const
{
  nsINode* imported = &aNode;
  rv = nsContentUtils::CheckSameOrigin(this, imported);
  if (rv.Failed()) {
    return nullptr;
  }

  switch (imported->NodeType()) {
    case nsIDOMNode::ATTRIBUTE_NODE:
    case nsIDOMNode::DOCUMENT_FRAGMENT_NODE:
    case nsIDOMNode::ELEMENT_NODE:
    case nsIDOMNode::PROCESSING_INSTRUCTION_NODE:
    case nsIDOMNode::TEXT_NODE:
    case nsIDOMNode::CDATA_SECTION_NODE:
    case nsIDOMNode::COMMENT_NODE:
    case nsIDOMNode::DOCUMENT_TYPE_NODE:
    {
      nsCOMPtr<nsINode> newNode;
      nsCOMArray<nsINode> nodesWithProperties;
      rv = nsNodeUtils::Clone(imported, aDeep, mNodeInfoManager,
                              nodesWithProperties, getter_AddRefs(newNode));
      if (rv.Failed()) {
        return nullptr;
      }

      nsIDocument *ownerDoc = imported->OwnerDoc();
      rv = nsNodeUtils::CallUserDataHandlers(nodesWithProperties, ownerDoc,
                                             nsIDOMUserDataHandler::NODE_IMPORTED,
                                             true);
      if (rv.Failed()) {
        return nullptr;
      }

      return newNode.forget();
    }
    default:
    {
      NS_WARNING("Don't know how to clone this nodetype for importNode.");

      rv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
    }
  }

  return nullptr;
}

NS_IMETHODIMP
nsDocument::LoadBindingDocument(const nsAString& aURI)
{
  ErrorResult rv;
  nsIDocument::LoadBindingDocument(aURI, rv);
  return rv.ErrorCode();
}

void
nsIDocument::LoadBindingDocument(const nsAString& aURI, ErrorResult& rv)
{
  nsCOMPtr<nsIURI> uri;
  rv = NS_NewURI(getter_AddRefs(uri), aURI,
                 mCharacterSet.get(),
                 GetDocBaseURI());
  if (rv.Failed()) {
    return;
  }

  // Figure out the right principal to use
  nsCOMPtr<nsIPrincipal> subject;
  nsIScriptSecurityManager* secMan = nsContentUtils::GetSecurityManager();
  if (secMan) {
    rv = secMan->GetSubjectPrincipal(getter_AddRefs(subject));
    if (rv.Failed()) {
      return;
    }
  }

  if (!subject) {
    // Fall back to our principal.  Or should we fall back to the null
    // principal?  The latter would just mean no binding loads....
    subject = NodePrincipal();
  }

  BindingManager()->LoadBindingDocument(this, uri, subject);
}

NS_IMETHODIMP
nsDocument::GetBindingParent(nsIDOMNode* aNode, nsIDOMElement** aResult)
{
  nsCOMPtr<nsINode> node = do_QueryInterface(aNode);
  NS_ENSURE_ARG_POINTER(node);

  Element* bindingParent = nsIDocument::GetBindingParent(*node);
  nsCOMPtr<nsIDOMElement> retval = do_QueryInterface(bindingParent);
  retval.forget(aResult);
  return NS_OK;
}

Element*
nsIDocument::GetBindingParent(nsINode& aNode)
{
  nsCOMPtr<nsIContent> content(do_QueryInterface(&aNode));
  if (!content)
    return nullptr;

  nsIContent* bindingParent = content->GetBindingParent();
  return bindingParent ? bindingParent->AsElement() : nullptr;
}

static Element*
GetElementByAttribute(nsIContent* aContent, nsIAtom* aAttrName,
                      const nsAString& aAttrValue, bool aUniversalMatch)
{
  if (aUniversalMatch ? aContent->HasAttr(kNameSpaceID_None, aAttrName) :
                        aContent->AttrValueIs(kNameSpaceID_None, aAttrName,
                                              aAttrValue, eCaseMatters)) {
    return aContent->AsElement();
  }

  for (nsIContent* child = aContent->GetFirstChild();
       child;
       child = child->GetNextSibling()) {

    Element* matchedElement =
      GetElementByAttribute(child, aAttrName, aAttrValue, aUniversalMatch);
    if (matchedElement)
      return matchedElement;
  }

  return nullptr;
}

Element*
nsDocument::GetAnonymousElementByAttribute(nsIContent* aElement,
                                           nsIAtom* aAttrName,
                                           const nsAString& aAttrValue) const
{
  nsINodeList* nodeList = BindingManager()->GetAnonymousNodesFor(aElement);
  if (!nodeList)
    return nullptr;

  uint32_t length = 0;
  nodeList->GetLength(&length);

  bool universalMatch = aAttrValue.EqualsLiteral("*");

  for (uint32_t i = 0; i < length; ++i) {
    nsIContent* current = nodeList->Item(i);
    Element* matchedElm =
      GetElementByAttribute(current, aAttrName, aAttrValue, universalMatch);
    if (matchedElm)
      return matchedElm;
  }

  return nullptr;
}

NS_IMETHODIMP
nsDocument::GetAnonymousElementByAttribute(nsIDOMElement* aElement,
                                           const nsAString& aAttrName,
                                           const nsAString& aAttrValue,
                                           nsIDOMElement** aResult)
{
  nsCOMPtr<Element> element = do_QueryInterface(aElement);
  NS_ENSURE_ARG_POINTER(element);

  Element* anonEl =
    nsIDocument::GetAnonymousElementByAttribute(*element, aAttrName,
                                                aAttrValue);
  nsCOMPtr<nsIDOMElement> retval = do_QueryInterface(anonEl);
  retval.forget(aResult);
  return NS_OK;
}

Element*
nsIDocument::GetAnonymousElementByAttribute(Element& aElement,
                                            const nsAString& aAttrName,
                                            const nsAString& aAttrValue)
{
  nsCOMPtr<nsIAtom> attribute = do_GetAtom(aAttrName);

  return GetAnonymousElementByAttribute(&aElement, attribute, aAttrValue);
}


NS_IMETHODIMP
nsDocument::GetAnonymousNodes(nsIDOMElement* aElement,
                              nsIDOMNodeList** aResult)
{
  *aResult = nullptr;

  nsCOMPtr<nsIContent> content(do_QueryInterface(aElement));
  return BindingManager()->GetAnonymousNodesFor(content, aResult);
}

nsINodeList*
nsIDocument::GetAnonymousNodes(Element& aElement)
{
  return BindingManager()->GetAnonymousNodesFor(&aElement);
}

NS_IMETHODIMP
nsDocument::CreateRange(nsIDOMRange** aReturn)
{
  ErrorResult rv;
  *aReturn = nsIDocument::CreateRange(rv).get();
  return rv.ErrorCode();
}

already_AddRefed<nsRange>
nsIDocument::CreateRange(ErrorResult& rv)
{
  nsRefPtr<nsRange> range = new nsRange(this);
  nsresult res = range->Set(this, 0, this, 0);
  if (NS_FAILED(res)) {
    rv.Throw(res);
    return nullptr;
  }

  return range.forget();
}

NS_IMETHODIMP
nsDocument::CreateNodeIterator(nsIDOMNode *aRoot,
                               uint32_t aWhatToShow,
                               nsIDOMNodeFilter *aFilter,
                               uint8_t aOptionalArgc,
                               nsIDOMNodeIterator **_retval)
{
  *_retval = nullptr;

  if (!aOptionalArgc) {
    aWhatToShow = nsIDOMNodeFilter::SHOW_ALL;
  }

  if (!aRoot) {
    return NS_ERROR_DOM_NOT_SUPPORTED_ERR;
  }

  nsCOMPtr<nsINode> root = do_QueryInterface(aRoot);
  NS_ENSURE_TRUE(root, NS_ERROR_UNEXPECTED);

  ErrorResult rv;
  NodeFilterHolder holder(aFilter);
  *_retval = nsIDocument::CreateNodeIterator(*root, aWhatToShow, holder,
                                             rv).get();
  return rv.ErrorCode();
}

already_AddRefed<NodeIterator>
nsIDocument::CreateNodeIterator(nsINode& aRoot, uint32_t aWhatToShow,
                                NodeFilter* aFilter,
                                ErrorResult& rv) const
{
  NodeFilterHolder holder(aFilter);
  return CreateNodeIterator(aRoot, aWhatToShow, holder, rv);
}

already_AddRefed<NodeIterator>
nsIDocument::CreateNodeIterator(nsINode& aRoot, uint32_t aWhatToShow,
                                const NodeFilterHolder& aFilter,
                                ErrorResult& rv) const
{
  nsINode* root = &aRoot;
  nsresult res = nsContentUtils::CheckSameOrigin(this, root);
  if (NS_FAILED(res)) {
    rv.Throw(res);
    return nullptr;
  }

  nsRefPtr<NodeIterator> iterator = new NodeIterator(root, aWhatToShow,
                                                     aFilter);
  return iterator.forget();
}

NS_IMETHODIMP
nsDocument::CreateTreeWalker(nsIDOMNode *aRoot,
                             uint32_t aWhatToShow,
                             nsIDOMNodeFilter *aFilter,
                             uint8_t aOptionalArgc,
                             nsIDOMTreeWalker **_retval)
{
  *_retval = nullptr;

  if (!aOptionalArgc) {
    aWhatToShow = nsIDOMNodeFilter::SHOW_ALL;
  }

  nsCOMPtr<nsINode> root = do_QueryInterface(aRoot);
  NS_ENSURE_TRUE(root, NS_ERROR_DOM_NOT_SUPPORTED_ERR);

  ErrorResult rv;
  NodeFilterHolder holder(aFilter);
  *_retval = nsIDocument::CreateTreeWalker(*root, aWhatToShow, holder,
                                           rv).get();
  return rv.ErrorCode();
}

already_AddRefed<TreeWalker>
nsIDocument::CreateTreeWalker(nsINode& aRoot, uint32_t aWhatToShow,
                              NodeFilter* aFilter,
                              ErrorResult& rv) const
{
  NodeFilterHolder holder(aFilter);
  return CreateTreeWalker(aRoot, aWhatToShow, holder, rv);
}

already_AddRefed<TreeWalker>
nsIDocument::CreateTreeWalker(nsINode& aRoot, uint32_t aWhatToShow,
                              const NodeFilterHolder& aFilter,
                              ErrorResult& rv) const
{
  nsINode* root = &aRoot;
  nsresult res = nsContentUtils::CheckSameOrigin(this, root);
  if (NS_FAILED(res)) {
    rv.Throw(res);
    return nullptr;
  }

  nsRefPtr<TreeWalker> walker = new TreeWalker(root, aWhatToShow, aFilter);
  return walker.forget();
}


NS_IMETHODIMP
nsDocument::GetDefaultView(nsIDOMWindow** aDefaultView)
{
  *aDefaultView = nullptr;
  nsCOMPtr<nsPIDOMWindow> win = GetWindow();
  win.forget(aDefaultView);
  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetLocation(nsIDOMLocation **_retval)
{
  *_retval = nsIDocument::GetLocation().get();
  return NS_OK;
}

already_AddRefed<nsIDOMLocation>
nsIDocument::GetLocation() const
{
  nsCOMPtr<nsIDOMWindow> w = do_QueryInterface(mScriptGlobalObject);

  if (!w) {
    return nullptr;
  }

  nsCOMPtr<nsIDOMLocation> loc;
  w->GetLocation(getter_AddRefs(loc));
  return loc.forget();
}

Element*
nsIDocument::GetHtmlElement() const
{
  Element* rootElement = GetRootElement();
  if (rootElement && rootElement->IsHTML(nsGkAtoms::html))
    return rootElement;
  return nullptr;
}

Element*
nsIDocument::GetHtmlChildElement(nsIAtom* aTag)
{
  Element* html = GetHtmlElement();
  if (!html)
    return nullptr;

  // Look for the element with aTag inside html. This needs to run
  // forwards to find the first such element.
  for (nsIContent* child = html->GetFirstChild();
       child;
       child = child->GetNextSibling()) {
    if (child->IsHTML(aTag))
      return child->AsElement();
  }
  return nullptr;
}

nsIContent*
nsDocument::GetTitleContent(uint32_t aNamespace)
{
  // mMayHaveTitleElement will have been set to true if any HTML or SVG
  // <title> element has been bound to this document. So if it's false,
  // we know there is nothing to do here. This avoids us having to search
  // the whole DOM if someone calls document.title on a large document
  // without a title.
  if (!mMayHaveTitleElement)
    return nullptr;

  nsRefPtr<nsContentList> list =
    NS_GetContentList(this, aNamespace, NS_LITERAL_STRING("title"));

  return list->Item(0, false);
}

void
nsDocument::GetTitleFromElement(uint32_t aNamespace, nsAString& aTitle)
{
  nsIContent* title = GetTitleContent(aNamespace);
  if (!title)
    return;
  nsContentUtils::GetNodeTextContent(title, false, aTitle);
}

NS_IMETHODIMP
nsDocument::GetTitle(nsAString& aTitle)
{
  nsString title;
  GetTitle(title);
  aTitle = title;
  return NS_OK;
}

void
nsDocument::GetTitle(nsString& aTitle)
{
  aTitle.Truncate();

  nsIContent *rootElement = GetRootElement();
  if (!rootElement)
    return;

  nsAutoString tmp;

  switch (rootElement->GetNameSpaceID()) {
#ifdef MOZ_XUL
    case kNameSpaceID_XUL:
      rootElement->GetAttr(kNameSpaceID_None, nsGkAtoms::title, tmp);
      break;
#endif
    case kNameSpaceID_SVG:
      if (rootElement->Tag() == nsGkAtoms::svg) {
        GetTitleFromElement(kNameSpaceID_SVG, tmp);
        break;
      } // else fall through
    default:
      GetTitleFromElement(kNameSpaceID_XHTML, tmp);
      break;
  }

  tmp.CompressWhitespace();
  aTitle = tmp;
}

NS_IMETHODIMP
nsDocument::SetTitle(const nsAString& aTitle)
{
  Element *rootElement = GetRootElement();
  if (!rootElement)
    return NS_OK;

  switch (rootElement->GetNameSpaceID()) {
    case kNameSpaceID_SVG:
      return NS_OK; // SVG doesn't support setting a title
#ifdef MOZ_XUL
    case kNameSpaceID_XUL:
      return rootElement->SetAttr(kNameSpaceID_None, nsGkAtoms::title,
                                  aTitle, true);
#endif
  }

  // Batch updates so that mutation events don't change "the title
  // element" under us
  mozAutoDocUpdate updateBatch(this, UPDATE_CONTENT_MODEL, true);

  nsIContent* title = GetTitleContent(kNameSpaceID_XHTML);
  if (!title) {
    Element *head = GetHeadElement();
    if (!head)
      return NS_OK;

    {
      nsCOMPtr<nsINodeInfo> titleInfo;
      titleInfo = mNodeInfoManager->GetNodeInfo(nsGkAtoms::title, nullptr,
                                                kNameSpaceID_XHTML,
                                                nsIDOMNode::ELEMENT_NODE);
      title = NS_NewHTMLTitleElement(titleInfo.forget());
      if (!title)
        return NS_OK;
    }

    head->AppendChildTo(title, true);
  }

  return nsContentUtils::SetNodeTextContent(title, aTitle, false);
}

void
nsDocument::SetTitle(const nsAString& aTitle, ErrorResult& rv)
{
  rv = SetTitle(aTitle);
}

void
nsDocument::NotifyPossibleTitleChange(bool aBoundTitleElement)
{
  NS_ASSERTION(!mInUnlinkOrDeletion || !aBoundTitleElement,
               "Setting a title while unlinking or destroying the element?");
  if (mInUnlinkOrDeletion) {
    return;
  }

  if (aBoundTitleElement) {
    mMayHaveTitleElement = true;
  }
  if (mPendingTitleChangeEvent.IsPending())
    return;

  nsRefPtr<nsRunnableMethod<nsDocument, void, false> > event =
    NS_NewNonOwningRunnableMethod(this,
      &nsDocument::DoNotifyPossibleTitleChange);
  nsresult rv = NS_DispatchToCurrentThread(event);
  if (NS_SUCCEEDED(rv)) {
    mPendingTitleChangeEvent = event;
  }
}

void
nsDocument::DoNotifyPossibleTitleChange()
{
  mPendingTitleChangeEvent.Forget();
  mHaveFiredTitleChange = true;

  nsAutoString title;
  GetTitle(title);

  nsCOMPtr<nsIPresShell> shell = GetShell();
  if (shell) {
    nsCOMPtr<nsISupports> container = shell->GetPresContext()->GetContainer();
    if (container) {
      nsCOMPtr<nsIBaseWindow> docShellWin = do_QueryInterface(container);
      if (docShellWin) {
        docShellWin->SetTitle(title.get());
      }
    }
  }

  // Fire a DOM event for the title change.
  nsContentUtils::DispatchChromeEvent(this, static_cast<nsIDocument*>(this),
                                      NS_LITERAL_STRING("DOMTitleChanged"),
                                      true, true);
}

already_AddRefed<nsIBoxObject>
nsDocument::GetBoxObjectFor(Element* aElement, ErrorResult& aRv)
{
  if (!aElement) {
    aRv.Throw(NS_ERROR_UNEXPECTED);
    return nullptr;
  }

  nsIDocument* doc = aElement->OwnerDoc();
  if (doc != this) {
    aRv.Throw(NS_ERROR_DOM_WRONG_DOCUMENT_ERR);
    return nullptr;
  }

  if (!mHasWarnedAboutBoxObjects && !aElement->IsXUL()) {
    mHasWarnedAboutBoxObjects = true;
    nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,
                                    "BoxObjects", this,
                                    nsContentUtils::eDOM_PROPERTIES,
                                    "UseOfGetBoxObjectForWarning");
  }

  if (!mBoxObjectTable) {
    mBoxObjectTable = new nsInterfaceHashtable<nsPtrHashKey<nsIContent>, nsPIBoxObject>;
    mBoxObjectTable->Init(12);
  } else {
    nsCOMPtr<nsPIBoxObject> boxObject = mBoxObjectTable->Get(aElement);
    if (boxObject) {
      return boxObject.forget();
    }
  }

  int32_t namespaceID;
  nsCOMPtr<nsIAtom> tag = BindingManager()->ResolveTag(aElement, &namespaceID);

  nsAutoCString contractID("@mozilla.org/layout/xul-boxobject");
  if (namespaceID == kNameSpaceID_XUL) {
    if (tag == nsGkAtoms::browser ||
        tag == nsGkAtoms::editor ||
        tag == nsGkAtoms::iframe)
      contractID += "-container";
    else if (tag == nsGkAtoms::menu)
      contractID += "-menu";
    else if (tag == nsGkAtoms::popup ||
             tag == nsGkAtoms::menupopup ||
             tag == nsGkAtoms::panel ||
             tag == nsGkAtoms::tooltip)
      contractID += "-popup";
    else if (tag == nsGkAtoms::tree)
      contractID += "-tree";
    else if (tag == nsGkAtoms::listbox)
      contractID += "-listbox";
    else if (tag == nsGkAtoms::scrollbox)
      contractID += "-scrollbox";
  }
  contractID += ";1";

  nsCOMPtr<nsPIBoxObject> boxObject(do_CreateInstance(contractID.get()));
  if (!boxObject) {
    aRv.Throw(NS_ERROR_FAILURE);
    return nullptr;
  }

  boxObject->Init(aElement);

  if (mBoxObjectTable) {
    mBoxObjectTable->Put(aElement, boxObject.get());
  }

  return boxObject.forget();
}

void
nsDocument::ClearBoxObjectFor(nsIContent* aContent)
{
  if (mBoxObjectTable) {
    nsPIBoxObject *boxObject = mBoxObjectTable->GetWeak(aContent);
    if (boxObject) {
      boxObject->Clear();
      mBoxObjectTable->Remove(aContent);
    }
  }
}

void
nsDocument::FlushSkinBindings()
{
  BindingManager()->FlushSkinBindings();
}

nsresult
nsDocument::InitializeFrameLoader(nsFrameLoader* aLoader)
{
  mInitializableFrameLoaders.RemoveElement(aLoader);
  // Don't even try to initialize.
  if (mInDestructor) {
    NS_WARNING("Trying to initialize a frame loader while"
               "document is being deleted");
    return NS_ERROR_FAILURE;
  }

  mInitializableFrameLoaders.AppendElement(aLoader);
  if (!mFrameLoaderRunner) {
    mFrameLoaderRunner =
      NS_NewRunnableMethod(this, &nsDocument::MaybeInitializeFinalizeFrameLoaders);
    NS_ENSURE_TRUE(mFrameLoaderRunner, NS_ERROR_OUT_OF_MEMORY);
    nsContentUtils::AddScriptRunner(mFrameLoaderRunner);
  }
  return NS_OK;
}

nsresult
nsDocument::FinalizeFrameLoader(nsFrameLoader* aLoader)
{
  mInitializableFrameLoaders.RemoveElement(aLoader);
  if (mInDestructor) {
    return NS_ERROR_FAILURE;
  }

  mFinalizableFrameLoaders.AppendElement(aLoader);
  if (!mFrameLoaderRunner) {
    mFrameLoaderRunner =
      NS_NewRunnableMethod(this, &nsDocument::MaybeInitializeFinalizeFrameLoaders);
    NS_ENSURE_TRUE(mFrameLoaderRunner, NS_ERROR_OUT_OF_MEMORY);
    nsContentUtils::AddScriptRunner(mFrameLoaderRunner);
  }
  return NS_OK;
}

void
nsDocument::MaybeInitializeFinalizeFrameLoaders()
{
  if (mDelayFrameLoaderInitialization || mUpdateNestLevel != 0) {
    // This method will be recalled when mUpdateNestLevel drops to 0,
    // or when !mDelayFrameLoaderInitialization.
    mFrameLoaderRunner = nullptr;
    return;
  }

  // We're not in an update, but it is not safe to run scripts, so
  // postpone frameloader initialization and finalization.
  if (!nsContentUtils::IsSafeToRunScript()) {
    if (!mInDestructor && !mFrameLoaderRunner &&
        (mInitializableFrameLoaders.Length() ||
         mFinalizableFrameLoaders.Length())) {
      mFrameLoaderRunner =
        NS_NewRunnableMethod(this, &nsDocument::MaybeInitializeFinalizeFrameLoaders);
      nsContentUtils::AddScriptRunner(mFrameLoaderRunner);
    }
    return;
  }
  mFrameLoaderRunner = nullptr;

  // Don't use a temporary array for mInitializableFrameLoaders, because
  // loading a frame may cause some other frameloader to be removed from the
  // array. But be careful to keep the loader alive when starting the load!
  while (mInitializableFrameLoaders.Length()) {
    nsRefPtr<nsFrameLoader> loader = mInitializableFrameLoaders[0];
    mInitializableFrameLoaders.RemoveElementAt(0);
    NS_ASSERTION(loader, "null frameloader in the array?");
    loader->ReallyStartLoading();
  }

  uint32_t length = mFinalizableFrameLoaders.Length();
  if (length > 0) {
    nsTArray<nsRefPtr<nsFrameLoader> > loaders;
    mFinalizableFrameLoaders.SwapElements(loaders);
    for (uint32_t i = 0; i < length; ++i) {
      loaders[i]->Finalize();
    }
  }
}

void
nsDocument::TryCancelFrameLoaderInitialization(nsIDocShell* aShell)
{
  uint32_t length = mInitializableFrameLoaders.Length();
  for (uint32_t i = 0; i < length; ++i) {
    if (mInitializableFrameLoaders[i]->GetExistingDocShell() == aShell) {
      mInitializableFrameLoaders.RemoveElementAt(i);
      return;
    }
  }
}

bool
nsDocument::FrameLoaderScheduledToBeFinalized(nsIDocShell* aShell)
{
  if (aShell) {
    uint32_t length = mFinalizableFrameLoaders.Length();
    for (uint32_t i = 0; i < length; ++i) {
      if (mFinalizableFrameLoaders[i]->GetExistingDocShell() == aShell) {
        return true;
      }
    }
  }
  return false;
}

nsIDocument*
nsDocument::RequestExternalResource(nsIURI* aURI,
                                    nsINode* aRequestingNode,
                                    ExternalResourceLoad** aPendingLoad)
{
  NS_PRECONDITION(aURI, "Must have a URI");
  NS_PRECONDITION(aRequestingNode, "Must have a node");
  if (mDisplayDocument) {
    return mDisplayDocument->RequestExternalResource(aURI,
                                                     aRequestingNode,
                                                     aPendingLoad);
  }

  return mExternalResourceMap.RequestResource(aURI, aRequestingNode,
                                              this, aPendingLoad);
}

void
nsDocument::EnumerateExternalResources(nsSubDocEnumFunc aCallback, void* aData)
{
  mExternalResourceMap.EnumerateResources(aCallback, aData);
}

nsSMILAnimationController*
nsDocument::GetAnimationController()
{
  // We create the animation controller lazily because most documents won't want
  // one and only SVG documents and the like will call this
  if (mAnimationController)
    return mAnimationController;
  // Refuse to create an Animation Controller for data documents.
  if (mLoadedAsData || mLoadedAsInteractiveData)
    return nullptr;

  mAnimationController = new nsSMILAnimationController(this);

  // If there's a presContext then check the animation mode and pause if
  // necessary.
  nsIPresShell *shell = GetShell();
  if (mAnimationController && shell) {
    nsPresContext *context = shell->GetPresContext();
    if (context &&
        context->ImageAnimationMode() == imgIContainer::kDontAnimMode) {
      mAnimationController->Pause(nsSMILTimeContainer::PAUSE_USERPREF);
    }
  }

  // If we're hidden (or being hidden), notify the newly-created animation
  // controller. (Skip this check for SVG-as-an-image documents, though,
  // because they don't get OnPageShow / OnPageHide calls).
  if (!mIsShowing && !mIsBeingUsedAsImage) {
    mAnimationController->OnPageHide();
  }

  return mAnimationController;
}

/**
 * Retrieve the "direction" property of the document.
 *
 * @lina 01/09/2001
 */
NS_IMETHODIMP
nsDocument::GetDir(nsAString& aDirection)
{
  nsIDocument::GetDir(aDirection);
  return NS_OK;
}

void
nsIDocument::GetDir(nsAString& aDirection) const
{
  aDirection.Truncate();
  Element* rootElement = GetHtmlElement();
  if (rootElement) {
    static_cast<nsGenericHTMLElement*>(rootElement)->GetDir(aDirection);
  }
}

/**
 * Set the "direction" property of the document.
 *
 * @lina 01/09/2001
 */
NS_IMETHODIMP
nsDocument::SetDir(const nsAString& aDirection)
{
  nsIDocument::SetDir(aDirection);
  return NS_OK;
}

void
nsIDocument::SetDir(const nsAString& aDirection)
{
  Element* rootElement = GetHtmlElement();
  if (rootElement) {
    rootElement->SetAttr(kNameSpaceID_None, nsGkAtoms::dir,
                         aDirection, true);
  }
}

NS_IMETHODIMP
nsDocument::GetInputEncoding(nsAString& aInputEncoding)
{
  nsIDocument::GetInputEncoding(aInputEncoding);
  return NS_OK;
}

void
nsIDocument::GetInputEncoding(nsAString& aInputEncoding)
{
  // Not const function, because WarnOnceAbout is not a const method
  WarnOnceAbout(eInputEncoding);
  if (mHaveInputEncoding) {
    return GetCharacterSet(aInputEncoding);
  }

  SetDOMStringToNull(aInputEncoding);
}

NS_IMETHODIMP
nsDocument::GetMozSyntheticDocument(bool *aSyntheticDocument)
{
  *aSyntheticDocument = mIsSyntheticDocument;
  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetDocumentURI(nsAString& aDocumentURI)
{
  nsString temp;
  nsIDocument::GetDocumentURI(temp);
  aDocumentURI = temp;
  return NS_OK;
}

void
nsIDocument::GetDocumentURI(nsString& aDocumentURI) const
{
  if (mDocumentURI) {
    nsAutoCString uri;
    mDocumentURI->GetSpec(uri);
    CopyUTF8toUTF16(uri, aDocumentURI);
  } else {
    aDocumentURI.Truncate();
  }
}

// Alias of above
NS_IMETHODIMP
nsDocument::GetURL(nsAString& aURL)
{
  return GetDocumentURI(aURL);
}

void
nsIDocument::GetURL(nsString& aURL) const
{
  return GetDocumentURI(aURL);
}

// readonly attribute DOMString compatMode;
// Returns "BackCompat" if we are in quirks mode, "CSS1Compat" if we are
// in almost standards or full standards mode. See bug 105640.  This was
// implemented to match MSIE's compatMode property.
NS_IMETHODIMP
nsDocument::GetCompatMode(nsAString& aCompatMode)
{
  nsString temp;
  nsIDocument::GetCompatMode(temp);
  aCompatMode = temp;
  return NS_OK;
}

void
nsIDocument::GetCompatMode(nsString& aCompatMode) const
{
  NS_ASSERTION(mCompatMode == eCompatibility_NavQuirks ||
               mCompatMode == eCompatibility_AlmostStandards ||
               mCompatMode == eCompatibility_FullStandards,
               "mCompatMode is neither quirks nor strict for this document");

  if (mCompatMode == eCompatibility_NavQuirks) {
    aCompatMode.AssignLiteral("BackCompat");
  } else {
    aCompatMode.AssignLiteral("CSS1Compat");
  }
}

static void BlastSubtreeToPieces(nsINode *aNode);

PLDHashOperator
BlastFunc(nsAttrHashKey::KeyType aKey, Attr *aData, void* aUserArg)
{
  nsCOMPtr<nsIAttribute> *attr =
    static_cast<nsCOMPtr<nsIAttribute>*>(aUserArg);

  *attr = aData;

  NS_ASSERTION(attr->get(),
               "non-nsIAttribute somehow made it into the hashmap?!");

  return PL_DHASH_STOP;
}

static void
BlastSubtreeToPieces(nsINode *aNode)
{
  if (aNode->IsElement()) {
    Element *element = aNode->AsElement();
    const nsDOMAttributeMap *map = element->GetAttributeMap();
    if (map) {
      nsCOMPtr<nsIAttribute> attr;
      while (map->Enumerate(BlastFunc, &attr) > 0) {
        BlastSubtreeToPieces(attr);

#ifdef DEBUG
        nsresult rv =
#endif
          element->UnsetAttr(attr->NodeInfo()->NamespaceID(),
                             attr->NodeInfo()->NameAtom(),
                             false);

        // XXX Should we abort here?
        NS_ASSERTION(NS_SUCCEEDED(rv), "Uhoh, UnsetAttr shouldn't fail!");
      }
    }
  }

  uint32_t count = aNode->GetChildCount();
  for (uint32_t i = 0; i < count; ++i) {
    BlastSubtreeToPieces(aNode->GetFirstChild());
    aNode->RemoveChildAt(0, false);
  }
}


class nsUserDataCaller : public nsRunnable
{
public:
  nsUserDataCaller(nsCOMArray<nsINode>& aNodesWithProperties,
                   nsIDocument* aOwnerDoc)
    : mNodesWithProperties(aNodesWithProperties),
      mOwnerDoc(aOwnerDoc)
  {
  }

  NS_IMETHOD Run()
  {
    nsNodeUtils::CallUserDataHandlers(mNodesWithProperties, mOwnerDoc,
                                      nsIDOMUserDataHandler::NODE_ADOPTED,
                                      false);
    return NS_OK;
  }

private:
  nsCOMArray<nsINode> mNodesWithProperties;
  nsCOMPtr<nsIDocument> mOwnerDoc;
};

NS_IMETHODIMP
nsDocument::AdoptNode(nsIDOMNode *aAdoptedNode, nsIDOMNode **aResult)
{
  *aResult = nullptr;

  nsCOMPtr<nsINode> adoptedNode = do_QueryInterface(aAdoptedNode);
  NS_ENSURE_TRUE(adoptedNode, NS_ERROR_UNEXPECTED);

  ErrorResult rv;
  nsINode* result = nsIDocument::AdoptNode(*adoptedNode, rv);
  if (rv.Failed()) {
    return rv.ErrorCode();
  }

  NS_ADDREF(*aResult = result->AsDOMNode());
  return NS_OK;
}

nsINode*
nsIDocument::AdoptNode(nsINode& aAdoptedNode, ErrorResult& rv)
{
  nsINode* adoptedNode = &aAdoptedNode;
  rv = nsContentUtils::CheckSameOrigin(this, adoptedNode);
  if (rv.Failed()) {
    return nullptr;
  }

  // Scope firing mutation events so that we don't carry any state that
  // might be stale
  {
    nsINode* parent = adoptedNode->GetParentNode();
    if (parent) {
      nsContentUtils::MaybeFireNodeRemoved(adoptedNode, parent,
                                           adoptedNode->OwnerDoc());
    }
  }

  nsAutoScriptBlocker scriptBlocker;

  switch (adoptedNode->NodeType()) {
    case nsIDOMNode::ATTRIBUTE_NODE:
    {
      // Remove from ownerElement.
      nsRefPtr<Attr> adoptedAttr = static_cast<Attr*>(adoptedNode);

      nsCOMPtr<Element> ownerElement = adoptedAttr->GetOwnerElement(rv);
      if (rv.Failed()) {
        return nullptr;
      }

      if (ownerElement) {
        nsRefPtr<Attr> newAttr =
          ownerElement->RemoveAttributeNode(*adoptedAttr, rv);
        if (rv.Failed()) {
          return nullptr;
        }

        newAttr.swap(adoptedAttr);
      }

      break;
    }
    case nsIDOMNode::DOCUMENT_FRAGMENT_NODE:
    case nsIDOMNode::ELEMENT_NODE:
    case nsIDOMNode::PROCESSING_INSTRUCTION_NODE:
    case nsIDOMNode::TEXT_NODE:
    case nsIDOMNode::CDATA_SECTION_NODE:
    case nsIDOMNode::COMMENT_NODE:
    case nsIDOMNode::DOCUMENT_TYPE_NODE:
    {
      // Don't allow adopting a node's anonymous subtree out from under it.
      if (adoptedNode->AsContent()->IsRootOfAnonymousSubtree()) {
        rv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
        return nullptr;
      }

      // We don't want to adopt an element into its own contentDocument or into
      // a descendant contentDocument, so we check if the frameElement of this
      // document or any of its parents is the adopted node or one of its
      // descendants.
      nsIDocument *doc = this;
      do {
        nsPIDOMWindow *win = doc->GetWindow();
        if (win) {
          nsCOMPtr<nsINode> node =
            do_QueryInterface(win->GetFrameElementInternal());
          if (node &&
              nsContentUtils::ContentIsDescendantOf(node, adoptedNode)) {
            rv.Throw(NS_ERROR_DOM_HIERARCHY_REQUEST_ERR);
            return nullptr;
          }
        }
      } while ((doc = doc->GetParentDocument()));

      // Remove from parent.
      nsCOMPtr<nsINode> parent = adoptedNode->GetParentNode();
      if (parent) {
        int32_t idx = parent->IndexOf(adoptedNode);
        MOZ_ASSERT(idx >= 0);
        parent->RemoveChildAt(idx, true);
      }

      break;
    }
    case nsIDOMNode::DOCUMENT_NODE:
    {
      rv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
      return nullptr;
    }
    default:
    {
      NS_WARNING("Don't know how to adopt this nodetype for adoptNode.");

      rv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
      return nullptr;
    }
  }

  nsCOMPtr<nsIDocument> oldDocument = adoptedNode->OwnerDoc();
  bool sameDocument = oldDocument == this;

  AutoJSContext cx;
  JS::Rooted<JSObject*> newScope(cx, nullptr);
  if (!sameDocument) {
    newScope = GetWrapper();
    if (!newScope && GetScopeObject() && GetScopeObject()->GetGlobalJSObject()) {
      // We need to pass some sort of scope object to WrapNative. It's kind of
      // irrelevant, given that we're passing aAllowWrapping = false, and
      // documents should always insist on being wrapped in an canonical
      // scope. But we try to pass something sane anyway.
      JS::Rooted<JSObject*> global(cx, GetScopeObject()->GetGlobalJSObject());

      JS::Rooted<JS::Value> v(cx);
      rv = nsContentUtils::WrapNative(cx, global, this, this, v.address(),
                                      nullptr, /* aAllowWrapping = */ false);
      if (rv.Failed())
        return nullptr;
      newScope = &v.toObject();
    }
  }

  nsCOMArray<nsINode> nodesWithProperties;
  rv = nsNodeUtils::Adopt(adoptedNode, sameDocument ? nullptr : mNodeInfoManager,
                          newScope, nodesWithProperties);
  if (rv.Failed()) {
    // Disconnect all nodes from their parents, since some have the old document
    // as their ownerDocument and some have this as their ownerDocument.
    BlastSubtreeToPieces(adoptedNode);

    if (!sameDocument && oldDocument) {
      uint32_t count = nodesWithProperties.Count();
      for (uint32_t j = 0; j < oldDocument->GetPropertyTableCount(); ++j) {
        for (uint32_t i = 0; i < count; ++i) {
          // Remove all properties.
          oldDocument->PropertyTable(j)->
            DeleteAllPropertiesFor(nodesWithProperties[i]);
        }
      }
    }

    return nullptr;
  }

  uint32_t count = nodesWithProperties.Count();
  if (!sameDocument && oldDocument) {
    for (uint32_t j = 0; j < oldDocument->GetPropertyTableCount(); ++j) {
      nsPropertyTable *oldTable = oldDocument->PropertyTable(j);
      nsPropertyTable *newTable = PropertyTable(j);
      for (uint32_t i = 0; i < count; ++i) {
        rv = oldTable->TransferOrDeleteAllPropertiesFor(nodesWithProperties[i],
                                                        newTable);
      }
    }

    if (rv.Failed()) {
      // Disconnect all nodes from their parents.
      BlastSubtreeToPieces(adoptedNode);

      return nullptr;
    }
  }

  if (nodesWithProperties.Count()) {
    nsContentUtils::AddScriptRunner(new nsUserDataCaller(nodesWithProperties,
                                                         this));
  }

  NS_ASSERTION(adoptedNode->OwnerDoc() == this,
               "Should still be in the document we just got adopted into");

  return adoptedNode;
}

nsViewportInfo
nsDocument::GetViewportInfo(uint32_t aDisplayWidth,
                            uint32_t aDisplayHeight)
{
  switch (mViewportType) {
  case DisplayWidthHeight:
    return nsViewportInfo(aDisplayWidth, aDisplayHeight);
  case Unknown:
  {
    nsAutoString viewport;
    GetHeaderData(nsGkAtoms::viewport, viewport);
    if (viewport.IsEmpty()) {
      // If the docType specifies that we are on a site optimized for mobile,
      // then we want to return specially crafted defaults for the viewport info.
      nsCOMPtr<nsIDOMDocumentType> docType;
      nsresult rv = GetDoctype(getter_AddRefs(docType));
      if (NS_SUCCEEDED(rv) && docType) {
        nsAutoString docId;
        rv = docType->GetPublicId(docId);
        if (NS_SUCCEEDED(rv)) {
          if ((docId.Find("WAP") != -1) ||
              (docId.Find("Mobile") != -1) ||
              (docId.Find("WML") != -1))
          {
            // We're making an assumption that the docType can't change here
            mViewportType = DisplayWidthHeight;
            nsViewportInfo ret(aDisplayWidth, aDisplayHeight);
            return ret;
          }
        }
      }

      nsAutoString handheldFriendly;
      GetHeaderData(nsGkAtoms::handheldFriendly, handheldFriendly);
      if (handheldFriendly.EqualsLiteral("true")) {
        mViewportType = DisplayWidthHeight;
        nsViewportInfo ret(aDisplayWidth, aDisplayHeight);
        return ret;
      }
    }

    nsAutoString minScaleStr;
    GetHeaderData(nsGkAtoms::viewport_minimum_scale, minScaleStr);

    nsresult errorCode;
    mScaleMinFloat = minScaleStr.ToFloat(&errorCode);

    if (NS_FAILED(errorCode)) {
      mScaleMinFloat = kViewportMinScale;
    }

    mScaleMinFloat = std::min((double)mScaleMinFloat, kViewportMaxScale);
    mScaleMinFloat = std::max((double)mScaleMinFloat, kViewportMinScale);

    nsAutoString maxScaleStr;
    GetHeaderData(nsGkAtoms::viewport_maximum_scale, maxScaleStr);

    // We define a special error code variable for the scale and max scale,
    // because they are used later (see the width calculations).
    nsresult scaleMaxErrorCode;
    mScaleMaxFloat = maxScaleStr.ToFloat(&scaleMaxErrorCode);

    if (NS_FAILED(scaleMaxErrorCode)) {
      mScaleMaxFloat = kViewportMaxScale;
    }

    mScaleMaxFloat = std::min((double)mScaleMaxFloat, kViewportMaxScale);
    mScaleMaxFloat = std::max((double)mScaleMaxFloat, kViewportMinScale);

    nsAutoString scaleStr;
    GetHeaderData(nsGkAtoms::viewport_initial_scale, scaleStr);

    nsresult scaleErrorCode;
    mScaleFloat = scaleStr.ToFloat(&scaleErrorCode);

    nsAutoString widthStr, heightStr;

    GetHeaderData(nsGkAtoms::viewport_height, heightStr);
    GetHeaderData(nsGkAtoms::viewport_width, widthStr);

    mAutoSize = false;

    if (widthStr.EqualsLiteral("device-width")) {
      mAutoSize = true;
    }

    if (widthStr.IsEmpty() &&
        (heightStr.EqualsLiteral("device-height") ||
         (mScaleFloat /* not adjusted for pixel ratio */ == 1.0)))
    {
      mAutoSize = true;
    }

    nsresult widthErrorCode, heightErrorCode;
    mViewportWidth = widthStr.ToInteger(&widthErrorCode);
    mViewportHeight = heightStr.ToInteger(&heightErrorCode);

    // If width or height has not been set to a valid number by this point,
    // fall back to a default value.
    mValidWidth = (!widthStr.IsEmpty() && NS_SUCCEEDED(widthErrorCode) && mViewportWidth > 0);
    mValidHeight = (!heightStr.IsEmpty() && NS_SUCCEEDED(heightErrorCode) && mViewportHeight > 0);


    mAllowZoom = true;
    nsAutoString userScalable;
    GetHeaderData(nsGkAtoms::viewport_user_scalable, userScalable);

    if ((userScalable.EqualsLiteral("0")) ||
        (userScalable.EqualsLiteral("no")) ||
        (userScalable.EqualsLiteral("false"))) {
      mAllowZoom = false;
    }

    mScaleStrEmpty = scaleStr.IsEmpty();
    mWidthStrEmpty = widthStr.IsEmpty();
    mValidScaleFloat = !scaleStr.IsEmpty() && NS_SUCCEEDED(scaleErrorCode);
    mValidMaxScale = !maxScaleStr.IsEmpty() && NS_SUCCEEDED(scaleMaxErrorCode);

    mViewportType = Specified;
  }
  case Specified:
  default:
    uint32_t width = mViewportWidth, height = mViewportHeight;

    if (!mValidWidth) {
      if (mValidHeight && aDisplayWidth > 0 && aDisplayHeight > 0) {
        width = uint32_t((height * aDisplayWidth) / aDisplayHeight);
      } else {
        width = Preferences::GetInt("browser.viewport.desktopWidth",
                                             kViewportDefaultScreenWidth);
      }
    }

    if (!mValidHeight) {
      if (aDisplayWidth > 0 && aDisplayHeight > 0) {
        height = uint32_t((width * aDisplayHeight) / aDisplayWidth);
      } else {
        height = width;
      }
    }
    // Now convert the scale into device pixels per CSS pixel.
    nsIWidget *widget = nsContentUtils::WidgetForDocument(this);
    double pixelRatio = widget ? widget->GetDefaultScale() : 1.0;
    float scaleFloat = mScaleFloat * pixelRatio;
    float scaleMinFloat= mScaleMinFloat * pixelRatio;
    float scaleMaxFloat = mScaleMaxFloat * pixelRatio;

    if (mAutoSize) {
      // aDisplayWidth and aDisplayHeight are in device pixels; convert them to
      // CSS pixels for the viewport size.
      width = aDisplayWidth / pixelRatio;
      height = aDisplayHeight / pixelRatio;
    }

    width = std::min(width, kViewportMaxWidth);
    width = std::max(width, kViewportMinWidth);

    // Also recalculate the default zoom, if it wasn't specified in the metadata,
    // and the width is specified.
    if (mScaleStrEmpty && !mWidthStrEmpty) {
      scaleFloat = std::max(scaleFloat, float(aDisplayWidth) / float(width));
    }

    height = std::min(height, kViewportMaxHeight);
    height = std::max(height, kViewportMinHeight);

    // We need to perform a conversion, but only if the initial or maximum
    // scale were set explicitly by the user.
    if (mValidScaleFloat) {
      width = std::max(width, (uint32_t)(aDisplayWidth / scaleFloat));
      height = std::max(height, (uint32_t)(aDisplayHeight / scaleFloat));
    } else if (mValidMaxScale) {
      width = std::max(width, (uint32_t)(aDisplayWidth / scaleMaxFloat));
      height = std::max(height, (uint32_t)(aDisplayHeight / scaleMaxFloat));
    }

    nsViewportInfo ret(scaleFloat, scaleMinFloat, scaleMaxFloat, width, height,
                       mAutoSize, mAllowZoom);
    return ret;
  }
}

nsEventListenerManager*
nsDocument::GetListenerManager(bool aCreateIfNotFound)
{
  if (!mListenerManager && aCreateIfNotFound) {
    mListenerManager =
      new nsEventListenerManager(static_cast<EventTarget*>(this));
    SetFlags(NODE_HAS_LISTENERMANAGER);
  }

  return mListenerManager;
}

nsresult
nsDocument::PreHandleEvent(nsEventChainPreVisitor& aVisitor)
{
  aVisitor.mCanHandle = true;
   // FIXME! This is a hack to make middle mouse paste working also in Editor.
   // Bug 329119
  aVisitor.mForceContentDispatch = true;

  // Load events must not propagate to |window| object, see bug 335251.
  if (aVisitor.mEvent->message != NS_LOAD) {
    nsGlobalWindow* window = static_cast<nsGlobalWindow*>(GetWindow());
    aVisitor.mParentTarget =
      window ? window->GetTargetForEventTargetChain() : nullptr;
  }
  return NS_OK;
}

NS_IMETHODIMP
nsDocument::CreateEvent(const nsAString& aEventType, nsIDOMEvent** aReturn)
{
  NS_ENSURE_ARG_POINTER(aReturn);
  ErrorResult rv;
  *aReturn = nsIDocument::CreateEvent(aEventType, rv).get();
  return rv.ErrorCode();
}

already_AddRefed<nsDOMEvent>
nsIDocument::CreateEvent(const nsAString& aEventType, ErrorResult& rv) const
{
  nsIPresShell *shell = GetShell();

  nsPresContext *presContext = nullptr;

  if (shell) {
    // Retrieve the context
    presContext = shell->GetPresContext();
  }

  // Create event even without presContext.
  nsCOMPtr<nsIDOMEvent> ev;
  rv =
    nsEventDispatcher::CreateEvent(const_cast<nsIDocument*>(this),
                                   presContext, nullptr, aEventType,
                                   getter_AddRefs(ev));
  return ev ? dont_AddRef(ev.forget().get()->InternalDOMEvent()) : nullptr;
}

void
nsDocument::FlushPendingNotifications(mozFlushType aType)
{
  nsDocumentOnStack dos(this);

  // We need to flush the sink for non-HTML documents (because the XML
  // parser still does insertion with deferred notifications).  We
  // also need to flush the sink if this is a layout-related flush, to
  // make sure that layout is started as needed.  But we can skip that
  // part if we have no presshell or if it's already done an initial
  // reflow.
  if ((!IsHTML() ||
       (aType > Flush_ContentAndNotify && mPresShell &&
        !mPresShell->DidInitialize())) &&
      (mParser || mWeakSink)) {
    nsCOMPtr<nsIContentSink> sink;
    if (mParser) {
      sink = mParser->GetContentSink();
    } else {
      sink = do_QueryReferent(mWeakSink);
      if (!sink) {
        mWeakSink = nullptr;
      }
    }
    // Determine if it is safe to flush the sink notifications
    // by determining if it safe to flush all the presshells.
    if (sink && (aType == Flush_Content || IsSafeToFlush())) {
      sink->FlushPendingNotifications(aType);
    }
  }

  // Should we be flushing pending binding constructors in here?

  if (aType <= Flush_ContentAndNotify) {
    // Nothing to do here
    return;
  }

  // If we have a parent we must flush the parent too to ensure that our
  // container is reflowed if its size was changed.  But if it's not safe to
  // flush ourselves, then don't flush the parent, since that can cause things
  // like resizes of our frame's widget, which we can't handle while flushing
  // is unsafe.
  // Since media queries mean that a size change of our container can
  // affect style, we need to promote a style flush on ourself to a
  // layout flush on our parent, since we need our container to be the
  // correct size to determine the correct style.
  if (mParentDocument && IsSafeToFlush()) {
    mozFlushType parentType = aType;
    if (aType >= Flush_Style)
      parentType = std::max(Flush_Layout, aType);
    mParentDocument->FlushPendingNotifications(parentType);
  }

  // We can optimize away getting our presshell and calling
  // FlushPendingNotifications on it if we don't need a flush of the sort we're
  // looking at.  The one exception is if mInFlush is true, because in that
  // case we might have set mNeedStyleFlush and mNeedLayoutFlush to false
  // already but the presshell hasn't actually done the corresponding work yet.
  // So if mInFlush and reentering this code, we need to flush the presshell.
  if (mNeedStyleFlush ||
      (mNeedLayoutFlush && aType >= Flush_InterruptibleLayout) ||
      aType >= Flush_Display ||
      mInFlush) {
    nsCOMPtr<nsIPresShell> shell = GetShell();
    if (shell) {
      mNeedStyleFlush = false;
      mNeedLayoutFlush = mNeedLayoutFlush && (aType < Flush_InterruptibleLayout);
      // mInFlush is a bitfield, so can't us AutoRestore here.  But we
      // need to keep track of multi-level reentry correctly, so need
      // to restore the old mInFlush value.
      bool oldInFlush = mInFlush;
      mInFlush = true;
      shell->FlushPendingNotifications(aType);
      mInFlush = oldInFlush;
    }
  }
}

static bool
Copy(nsIDocument* aDocument, void* aData)
{
  nsTArray<nsCOMPtr<nsIDocument> >* resources =
    static_cast<nsTArray<nsCOMPtr<nsIDocument> >* >(aData);
  resources->AppendElement(aDocument);
  return true;
}

void
nsDocument::FlushExternalResources(mozFlushType aType)
{
  NS_ASSERTION(aType >= Flush_Style,
    "should only need to flush for style or higher in external resources");
  if (GetDisplayDocument()) {
    return;
  }
  nsTArray<nsCOMPtr<nsIDocument> > resources;
  EnumerateExternalResources(Copy, &resources);

  for (uint32_t i = 0; i < resources.Length(); i++) {
    resources[i]->FlushPendingNotifications(aType);
  }
}

void
nsDocument::SetXMLDeclaration(const PRUnichar *aVersion,
                              const PRUnichar *aEncoding,
                              const int32_t aStandalone)
{
  if (!aVersion || *aVersion == '\0') {
    mXMLDeclarationBits = 0;
    return;
  }

  mXMLDeclarationBits = XML_DECLARATION_BITS_DECLARATION_EXISTS;

  if (aEncoding && *aEncoding != '\0') {
    mXMLDeclarationBits |= XML_DECLARATION_BITS_ENCODING_EXISTS;
  }

  if (aStandalone == 1) {
    mXMLDeclarationBits |= XML_DECLARATION_BITS_STANDALONE_EXISTS |
                           XML_DECLARATION_BITS_STANDALONE_YES;
  }
  else if (aStandalone == 0) {
    mXMLDeclarationBits |= XML_DECLARATION_BITS_STANDALONE_EXISTS;
  }
}

void
nsDocument::GetXMLDeclaration(nsAString& aVersion, nsAString& aEncoding,
                              nsAString& aStandalone)
{
  aVersion.Truncate();
  aEncoding.Truncate();
  aStandalone.Truncate();

  if (!(mXMLDeclarationBits & XML_DECLARATION_BITS_DECLARATION_EXISTS)) {
    return;
  }

  // always until we start supporting 1.1 etc.
  aVersion.AssignLiteral("1.0");

  if (mXMLDeclarationBits & XML_DECLARATION_BITS_ENCODING_EXISTS) {
    // This is what we have stored, not necessarily what was written
    // in the original
    GetCharacterSet(aEncoding);
  }

  if (mXMLDeclarationBits & XML_DECLARATION_BITS_STANDALONE_EXISTS) {
    if (mXMLDeclarationBits & XML_DECLARATION_BITS_STANDALONE_YES) {
      aStandalone.AssignLiteral("yes");
    } else {
      aStandalone.AssignLiteral("no");
    }
  }
}

bool
nsDocument::IsScriptEnabled()
{
  // If this document is sandboxed without 'allow-scripts'
  // script is not enabled
  if (mSandboxFlags & SANDBOXED_SCRIPTS) {
    return false;
  }

  nsCOMPtr<nsIScriptSecurityManager> sm(do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID));
  NS_ENSURE_TRUE(sm, false);

  nsCOMPtr<nsIScriptGlobalObject> globalObject = do_QueryInterface(GetWindow());
  NS_ENSURE_TRUE(globalObject, false);

  nsIScriptContext *scriptContext = globalObject->GetContext();
  NS_ENSURE_TRUE(scriptContext, false);

  AutoPushJSContext cx(scriptContext->GetNativeContext());
  NS_ENSURE_TRUE(cx, false);

  bool enabled;
  nsresult rv = sm->CanExecuteScripts(cx, NodePrincipal(), &enabled);
  NS_ENSURE_SUCCESS(rv, false);
  return enabled;
}

nsRadioGroupStruct*
nsDocument::GetRadioGroupInternal(const nsAString& aName) const
{
#ifdef DEBUG
  if (IsHTML()) {
    nsAutoString lcName;
    ToLowerCase(aName, lcName);
    MOZ_ASSERT(aName == lcName);
  }
#endif

  nsRadioGroupStruct* radioGroup;
  if (!mRadioGroups.Get(aName, &radioGroup)) {
    return nullptr;
  }

  return radioGroup;
}

nsRadioGroupStruct*
nsDocument::GetRadioGroup(const nsAString& aName) const
{
  nsAutoString tmKey(aName);
  if (IsHTML()) {
    ToLowerCase(tmKey); //should case-insensitive.
  }

  return GetRadioGroupInternal(tmKey);
}

nsRadioGroupStruct*
nsDocument::GetOrCreateRadioGroup(const nsAString& aName)
{
  nsAutoString tmKey(aName);
  if (IsHTML()) {
    ToLowerCase(tmKey); //should case-insensitive.
  }

  if (nsRadioGroupStruct* radioGroup = GetRadioGroupInternal(tmKey)) {
    return radioGroup;
  }

  nsAutoPtr<nsRadioGroupStruct> newRadioGroup(new nsRadioGroupStruct());
  mRadioGroups.Put(tmKey, newRadioGroup);

  return newRadioGroup.forget();
}

void
nsDocument::SetCurrentRadioButton(const nsAString& aName,
                                  nsIDOMHTMLInputElement* aRadio)
{
  nsRadioGroupStruct* radioGroup = GetOrCreateRadioGroup(aName);
  radioGroup->mSelectedRadioButton = aRadio;
}

nsIDOMHTMLInputElement*
nsDocument::GetCurrentRadioButton(const nsAString& aName)
{
  return GetOrCreateRadioGroup(aName)->mSelectedRadioButton;
}

NS_IMETHODIMP
nsDocument::GetNextRadioButton(const nsAString& aName,
                               const bool aPrevious,
                               nsIDOMHTMLInputElement*  aFocusedRadio,
                               nsIDOMHTMLInputElement** aRadioOut)
{
  // XXX Can we combine the HTML radio button method impls of
  //     nsDocument and nsHTMLFormControl?
  // XXX Why is HTML radio button stuff in nsDocument, as
  //     opposed to nsHTMLDocument?
  *aRadioOut = nullptr;

  nsRadioGroupStruct* radioGroup = GetOrCreateRadioGroup(aName);

  // Return the radio button relative to the focused radio button.
  // If no radio is focused, get the radio relative to the selected one.
  nsCOMPtr<nsIDOMHTMLInputElement> currentRadio;
  if (aFocusedRadio) {
    currentRadio = aFocusedRadio;
  }
  else {
    currentRadio = radioGroup->mSelectedRadioButton;
    if (!currentRadio) {
      return NS_ERROR_FAILURE;
    }
  }
  nsCOMPtr<nsIFormControl> radioControl(do_QueryInterface(currentRadio));
  int32_t index = radioGroup->mRadioButtons.IndexOf(radioControl);
  if (index < 0) {
    return NS_ERROR_FAILURE;
  }

  int32_t numRadios = radioGroup->mRadioButtons.Count();
  bool disabled;
  nsCOMPtr<nsIDOMHTMLInputElement> radio;
  do {
    if (aPrevious) {
      if (--index < 0) {
        index = numRadios -1;
      }
    }
    else if (++index >= numRadios) {
      index = 0;
    }
    radio = do_QueryInterface(radioGroup->mRadioButtons[index]);
    NS_ASSERTION(radio, "mRadioButtons holding a non-radio button");
    radio->GetDisabled(&disabled);
  } while (disabled && radio != currentRadio);

  NS_IF_ADDREF(*aRadioOut = radio);
  return NS_OK;
}

void
nsDocument::AddToRadioGroup(const nsAString& aName,
                            nsIFormControl* aRadio)
{
  nsRadioGroupStruct* radioGroup = GetOrCreateRadioGroup(aName);
  radioGroup->mRadioButtons.AppendObject(aRadio);

  nsCOMPtr<nsIContent> element = do_QueryInterface(aRadio);
  NS_ASSERTION(element, "radio controls have to be content elements");
  if (element->HasAttr(kNameSpaceID_None, nsGkAtoms::required)) {
    radioGroup->mRequiredRadioCount++;
  }
}

void
nsDocument::RemoveFromRadioGroup(const nsAString& aName,
                                 nsIFormControl* aRadio)
{
  nsRadioGroupStruct* radioGroup = GetOrCreateRadioGroup(aName);
  radioGroup->mRadioButtons.RemoveObject(aRadio);

  nsCOMPtr<nsIContent> element = do_QueryInterface(aRadio);
  NS_ASSERTION(element, "radio controls have to be content elements");
  if (element->HasAttr(kNameSpaceID_None, nsGkAtoms::required)) {
    NS_ASSERTION(radioGroup->mRequiredRadioCount != 0,
                 "mRequiredRadioCount about to wrap below 0!");
    radioGroup->mRequiredRadioCount--;
  }
}

NS_IMETHODIMP
nsDocument::WalkRadioGroup(const nsAString& aName,
                           nsIRadioVisitor* aVisitor,
                           bool aFlushContent)
{
  nsRadioGroupStruct* radioGroup = GetOrCreateRadioGroup(aName);

  for (int i = 0; i < radioGroup->mRadioButtons.Count(); i++) {
    if (!aVisitor->Visit(radioGroup->mRadioButtons[i])) {
      return NS_OK;
    }
  }

  return NS_OK;
}

uint32_t
nsDocument::GetRequiredRadioCount(const nsAString& aName) const
{
  nsRadioGroupStruct* radioGroup = GetRadioGroup(aName);
  return radioGroup ? radioGroup->mRequiredRadioCount : 0;
}

void
nsDocument::RadioRequiredChanged(const nsAString& aName, nsIFormControl* aRadio)
{
  nsRadioGroupStruct* radioGroup = GetOrCreateRadioGroup(aName);

  nsCOMPtr<nsIContent> element = do_QueryInterface(aRadio);
  NS_ASSERTION(element, "radio controls have to be content elements");
  if (element->HasAttr(kNameSpaceID_None, nsGkAtoms::required)) {
    radioGroup->mRequiredRadioCount++;
  } else {
    NS_ASSERTION(radioGroup->mRequiredRadioCount != 0,
                 "mRequiredRadioCount about to wrap below 0!");
    radioGroup->mRequiredRadioCount--;
  }
}

bool
nsDocument::GetValueMissingState(const nsAString& aName) const
{
  nsRadioGroupStruct* radioGroup = GetRadioGroup(aName);
  return radioGroup && radioGroup->mGroupSuffersFromValueMissing;
}

void
nsDocument::SetValueMissingState(const nsAString& aName, bool aValue)
{
  nsRadioGroupStruct* radioGroup = GetOrCreateRadioGroup(aName);
  radioGroup->mGroupSuffersFromValueMissing = aValue;
}

void
nsDocument::RetrieveRelevantHeaders(nsIChannel *aChannel)
{
  nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(aChannel);
  PRTime modDate = 0;
  nsresult rv;

  if (httpChannel) {
    nsAutoCString tmp;
    rv = httpChannel->GetResponseHeader(NS_LITERAL_CSTRING("last-modified"),
                                        tmp);

    if (NS_SUCCEEDED(rv)) {
      PRTime time;
      PRStatus st = PR_ParseTimeString(tmp.get(), true, &time);
      if (st == PR_SUCCESS) {
        modDate = time;
      }
    }

    // The misspelled key 'referer' is as per the HTTP spec
    rv = httpChannel->GetRequestHeader(NS_LITERAL_CSTRING("referer"),
                                       mReferrer);
    if (NS_FAILED(rv)) {
      mReferrer.Truncate();
    }

    static const char *const headers[] = {
      "default-style",
      "content-style-type",
      "content-language",
      "content-disposition",
      "refresh",
      "x-dns-prefetch-control",
      "x-frame-options",
      // add more http headers if you need
      // XXXbz don't add content-location support without reading bug
      // 238654 and its dependencies/dups first.
      0
    };

    nsAutoCString headerVal;
    const char *const *name = headers;
    while (*name) {
      rv =
        httpChannel->GetResponseHeader(nsDependentCString(*name), headerVal);
      if (NS_SUCCEEDED(rv) && !headerVal.IsEmpty()) {
        nsCOMPtr<nsIAtom> key = do_GetAtom(*name);
        SetHeaderData(key, NS_ConvertASCIItoUTF16(headerVal));
      }
      ++name;
    }
  } else {
    nsCOMPtr<nsIFileChannel> fileChannel = do_QueryInterface(aChannel);
    if (fileChannel) {
      nsCOMPtr<nsIFile> file;
      fileChannel->GetFile(getter_AddRefs(file));
      if (file) {
        PRTime msecs;
        rv = file->GetLastModifiedTime(&msecs);

        if (NS_SUCCEEDED(rv)) {
          modDate = msecs * int64_t(PR_USEC_PER_MSEC);
        }
      }
    } else {
      nsAutoCString contentDisp;
      rv = aChannel->GetContentDispositionHeader(contentDisp);
      if (NS_SUCCEEDED(rv)) {
        SetHeaderData(nsGkAtoms::headerContentDisposition,
                      NS_ConvertASCIItoUTF16(contentDisp));
      }
    }
  }

  if (modDate == 0) {
    // We got nothing from our attempt to ask nsIFileChannel and
    // nsIHttpChannel for the last modified time. Return the current
    // time.
    modDate = PR_Now();
  }

  mLastModified.Truncate();
  if (modDate != 0) {
    PRExplodedTime prtime;
    PR_ExplodeTime(modDate, PR_LocalTimeParameters, &prtime);
    // "MM/DD/YYYY hh:mm:ss"
    char formatedTime[24];
    if (PR_snprintf(formatedTime, sizeof(formatedTime),
                    "%02ld/%02ld/%04hd %02ld:%02ld:%02ld",
                    prtime.tm_month + 1, prtime.tm_mday, prtime.tm_year,
                    prtime.tm_hour     ,  prtime.tm_min,  prtime.tm_sec)) {
      CopyASCIItoUTF16(nsDependentCString(formatedTime), mLastModified);
    }
  }
}

nsresult
nsDocument::CreateElem(const nsAString& aName, nsIAtom *aPrefix, int32_t aNamespaceID,
                       nsIContent **aResult)
{
#ifdef DEBUG
  nsAutoString qName;
  if (aPrefix) {
    aPrefix->ToString(qName);
    qName.Append(':');
  }
  qName.Append(aName);

  // Note: "a:b:c" is a valid name in non-namespaces XML, and
  // nsDocument::CreateElement can call us with such a name and no prefix,
  // which would cause an error if we just used true here.
  bool nsAware = aPrefix != nullptr || aNamespaceID != GetDefaultNamespaceID();
  NS_ASSERTION(NS_SUCCEEDED(nsContentUtils::CheckQName(qName, nsAware)),
               "Don't pass invalid prefixes to nsDocument::CreateElem, "
               "check caller.");
#endif

  *aResult = nullptr;

  nsCOMPtr<nsINodeInfo> nodeInfo;
  mNodeInfoManager->GetNodeInfo(aName, aPrefix, aNamespaceID,
                                nsIDOMNode::ELEMENT_NODE,
                                getter_AddRefs(nodeInfo));
  NS_ENSURE_TRUE(nodeInfo, NS_ERROR_OUT_OF_MEMORY);

  return NS_NewElement(aResult, nodeInfo.forget(), NOT_FROM_PARSER);
}

bool
nsDocument::IsSafeToFlush() const
{
  nsIPresShell* shell = GetShell();
  if (!shell)
    return true;

  return shell->IsSafeToFlush();
}

void
nsDocument::Sanitize()
{
  // Sanitize the document by resetting all password fields and any form
  // fields with autocomplete=off to their default values.  We do this now,
  // instead of when the presentation is restored, to offer some protection
  // in case there is ever an exploit that allows a cached document to be
  // accessed from a different document.

  // First locate all input elements, regardless of whether they are
  // in a form, and reset the password and autocomplete=off elements.

  nsRefPtr<nsContentList> nodes = GetElementsByTagName(NS_LITERAL_STRING("input"));

  nsCOMPtr<nsIContent> item;
  nsAutoString value;

  uint32_t length = nodes->Length(true);
  for (uint32_t i = 0; i < length; ++i) {
    NS_ASSERTION(nodes->Item(i), "null item in node list!");

    nsCOMPtr<nsIDOMHTMLInputElement> input = do_QueryInterface(nodes->Item(i));
    if (!input)
      continue;

    bool resetValue = false;

    input->GetAttribute(NS_LITERAL_STRING("autocomplete"), value);
    if (value.LowerCaseEqualsLiteral("off")) {
      resetValue = true;
    } else {
      input->GetType(value);
      if (value.LowerCaseEqualsLiteral("password"))
        resetValue = true;
    }

    if (resetValue) {
      nsCOMPtr<nsIFormControl> fc = do_QueryInterface(input);
      fc->Reset();
    }
  }

  // Now locate all _form_ elements that have autocomplete=off and reset them
  nodes = GetElementsByTagName(NS_LITERAL_STRING("form"));

  length = nodes->Length(true);
  for (uint32_t i = 0; i < length; ++i) {
    NS_ASSERTION(nodes->Item(i), "null item in nodelist");

    nsCOMPtr<nsIDOMHTMLFormElement> form = do_QueryInterface(nodes->Item(i));
    if (!form)
      continue;

    form->GetAttribute(NS_LITERAL_STRING("autocomplete"), value);
    if (value.LowerCaseEqualsLiteral("off"))
      form->Reset();
  }
}

struct SubDocEnumArgs
{
  nsIDocument::nsSubDocEnumFunc callback;
  void *data;
};

static PLDHashOperator
SubDocHashEnum(PLDHashTable *table, PLDHashEntryHdr *hdr,
               uint32_t number, void *arg)
{
  SubDocMapEntry *entry = static_cast<SubDocMapEntry*>(hdr);
  SubDocEnumArgs *args = static_cast<SubDocEnumArgs*>(arg);

  nsIDocument *subdoc = entry->mSubDocument;
  bool next = subdoc ? args->callback(subdoc, args->data) : true;

  return next ? PL_DHASH_NEXT : PL_DHASH_STOP;
}

void
nsDocument::EnumerateSubDocuments(nsSubDocEnumFunc aCallback, void *aData)
{
  if (mSubDocuments) {
    SubDocEnumArgs args = { aCallback, aData };
    PL_DHashTableEnumerate(mSubDocuments, SubDocHashEnum, &args);
  }
}

static PLDHashOperator
CanCacheSubDocument(PLDHashTable *table, PLDHashEntryHdr *hdr,
                    uint32_t number, void *arg)
{
  SubDocMapEntry *entry = static_cast<SubDocMapEntry*>(hdr);
  bool *canCacheArg = static_cast<bool*>(arg);

  nsIDocument *subdoc = entry->mSubDocument;

  // The aIgnoreRequest we were passed is only for us, so don't pass it on.
  bool canCache = subdoc ? subdoc->CanSavePresentation(nullptr) : false;
  if (!canCache) {
    *canCacheArg = false;
    return PL_DHASH_STOP;
  }

  return PL_DHASH_NEXT;
}

#ifdef DEBUG_bryner
#define DEBUG_PAGE_CACHE
#endif

bool
nsDocument::CanSavePresentation(nsIRequest *aNewRequest)
{
  if (EventHandlingSuppressed()) {
    return false;
  }

  nsPIDOMWindow* win = GetInnerWindow();
  if (win && win->TimeoutSuspendCount()) {
    return false;
  }

  // Check our event listener manager for unload/beforeunload listeners.
  nsCOMPtr<EventTarget> piTarget = do_QueryInterface(mScriptGlobalObject);
  if (piTarget) {
    nsEventListenerManager* manager =
      piTarget->GetListenerManager(false);
    if (manager && manager->HasUnloadListeners()) {
      return false;
    }
  }

  // Check if we have pending network requests
  nsCOMPtr<nsILoadGroup> loadGroup = GetDocumentLoadGroup();
  if (loadGroup) {
    nsCOMPtr<nsISimpleEnumerator> requests;
    loadGroup->GetRequests(getter_AddRefs(requests));

    bool hasMore = false;

    // We want to bail out if we have any requests other than aNewRequest (or
    // in the case when aNewRequest is a part of a multipart response the base
    // channel the multipart response is coming in on).
    nsCOMPtr<nsIChannel> baseChannel;
    nsCOMPtr<nsIMultiPartChannel> part(do_QueryInterface(aNewRequest));
    if (part) {
      part->GetBaseChannel(getter_AddRefs(baseChannel));
    }

    while (NS_SUCCEEDED(requests->HasMoreElements(&hasMore)) && hasMore) {
      nsCOMPtr<nsISupports> elem;
      requests->GetNext(getter_AddRefs(elem));

      nsCOMPtr<nsIRequest> request = do_QueryInterface(elem);
      if (request && request != aNewRequest && request != baseChannel) {
#ifdef DEBUG_PAGE_CACHE
        nsAutoCString requestName, docSpec;
        request->GetName(requestName);
        if (mDocumentURI)
          mDocumentURI->GetSpec(docSpec);

        printf("document %s has request %s\n",
               docSpec.get(), requestName.get());
#endif
        return false;
      }
    }
  }

  // Check if we have running offline storage transactions
  quota::QuotaManager* quotaManager =
    win ? quota::QuotaManager::Get() : nullptr;
  if (quotaManager && quotaManager->HasOpenTransactions(win)) {
   return false;
  }

#ifdef MOZ_WEBRTC
  // Check if we have active PeerConnections
  nsCOMPtr<IPeerConnectionManager> pcManager =
    do_GetService(IPEERCONNECTION_MANAGER_CONTRACTID);

  if (pcManager && win) {
    bool active;
    pcManager->HasActivePeerConnection(win->WindowID(), &active);
    if (active) {
      return false;
    }
  }
#endif // MOZ_WEBRTC

  bool canCache = true;
  if (mSubDocuments)
    PL_DHashTableEnumerate(mSubDocuments, CanCacheSubDocument, &canCache);

  return canCache;
}

void
nsDocument::Destroy()
{
  // The ContentViewer wants to release the document now.  So, tell our content
  // to drop any references to the document so that it can be destroyed.
  if (mIsGoingAway)
    return;

  mIsGoingAway = true;

  RemovedFromDocShell();

  bool oldVal = mInUnlinkOrDeletion;
  mInUnlinkOrDeletion = true;
  uint32_t i, count = mChildren.ChildCount();
  for (i = 0; i < count; ++i) {
    mChildren.ChildAt(i)->DestroyContent();
  }
  mInUnlinkOrDeletion = oldVal;

  mLayoutHistoryState = nullptr;

  // Shut down our external resource map.  We might not need this for
  // leak-fixing if we fix nsDocumentViewer to do cycle-collection, but
  // tearing down all those frame trees right now is the right thing to do.
  mExternalResourceMap.Shutdown();

  mCustomPrototypes.Clear();

  // XXX We really should let cycle collection do this, but that currently still
  //     leaks (see https://bugzilla.mozilla.org/show_bug.cgi?id=406684).
  nsContentUtils::ReleaseWrapper(static_cast<nsINode*>(this), this);
}

void
nsDocument::RemovedFromDocShell()
{
  if (mRemovedFromDocShell)
    return;

  mRemovedFromDocShell = true;
  EnumerateFreezableElements(NotifyActivityChanged, nullptr);

  uint32_t i, count = mChildren.ChildCount();
  for (i = 0; i < count; ++i) {
    mChildren.ChildAt(i)->SaveSubtreeState();
  }
}

already_AddRefed<nsILayoutHistoryState>
nsDocument::GetLayoutHistoryState() const
{
  nsCOMPtr<nsILayoutHistoryState> state;
  if (!mScriptGlobalObject) {
    state = mLayoutHistoryState;
  } else {
    nsCOMPtr<nsIDocShell> docShell(do_QueryReferent(mDocumentContainer));
    if (docShell) {
      docShell->GetLayoutHistoryState(getter_AddRefs(state));
    }
  }

  return state.forget();
}

void
nsDocument::EnsureOnloadBlocker()
{
  // If mScriptGlobalObject is null, we shouldn't be messing with the loadgroup
  // -- it's not ours.
  if (mOnloadBlockCount != 0 && mScriptGlobalObject) {
    nsCOMPtr<nsILoadGroup> loadGroup = GetDocumentLoadGroup();
    if (loadGroup) {
      // Check first to see if mOnloadBlocker is in the loadgroup.
      nsCOMPtr<nsISimpleEnumerator> requests;
      loadGroup->GetRequests(getter_AddRefs(requests));

      bool hasMore = false;
      while (NS_SUCCEEDED(requests->HasMoreElements(&hasMore)) && hasMore) {
        nsCOMPtr<nsISupports> elem;
        requests->GetNext(getter_AddRefs(elem));
        nsCOMPtr<nsIRequest> request = do_QueryInterface(elem);
        if (request && request == mOnloadBlocker) {
          return;
        }
      }

      // Not in the loadgroup, so add it.
      loadGroup->AddRequest(mOnloadBlocker, nullptr);
    }
  }
}

void
nsDocument::AsyncBlockOnload()
{
  while (mAsyncOnloadBlockCount) {
    --mAsyncOnloadBlockCount;
    BlockOnload();
  }
}

void
nsDocument::BlockOnload()
{
  if (mDisplayDocument) {
    mDisplayDocument->BlockOnload();
    return;
  }

  // If mScriptGlobalObject is null, we shouldn't be messing with the loadgroup
  // -- it's not ours.
  if (mOnloadBlockCount == 0 && mScriptGlobalObject) {
    if (!nsContentUtils::IsSafeToRunScript()) {
      // Because AddRequest may lead to OnStateChange calls in chrome,
      // block onload only when there are no script blockers.
      ++mAsyncOnloadBlockCount;
      if (mAsyncOnloadBlockCount == 1) {
        bool success = nsContentUtils::AddScriptRunner(
          NS_NewRunnableMethod(this, &nsDocument::AsyncBlockOnload));

        // The script runner shouldn't fail to add. But if somebody broke
        // something and it does, we'll thrash at 100% cpu forever. The best
        // response is just to ignore the onload blocking request. See bug 579535.
        if (!success) {
          NS_WARNING("Disaster! Onload blocking script runner failed to add - expect bad things!");
          mAsyncOnloadBlockCount = 0;
        }
      }
      return;
    }
    nsCOMPtr<nsILoadGroup> loadGroup = GetDocumentLoadGroup();
    if (loadGroup) {
      loadGroup->AddRequest(mOnloadBlocker, nullptr);
    }
  }
  ++mOnloadBlockCount;
}

void
nsDocument::UnblockOnload(bool aFireSync)
{
  if (mDisplayDocument) {
    mDisplayDocument->UnblockOnload(aFireSync);
    return;
  }

  if (mOnloadBlockCount == 0 && mAsyncOnloadBlockCount == 0) {
    NS_NOTREACHED("More UnblockOnload() calls than BlockOnload() calls; dropping call");
    return;
  }

  --mOnloadBlockCount;

  if (mOnloadBlockCount == 0) {
    if (mScriptGlobalObject) {
      // Only manipulate the loadgroup in this case, because if mScriptGlobalObject
      // is null, it's not ours.
      if (aFireSync && mAsyncOnloadBlockCount == 0) {
        // Increment mOnloadBlockCount, since DoUnblockOnload will decrement it
        ++mOnloadBlockCount;
        DoUnblockOnload();
      } else {
        PostUnblockOnloadEvent();
      }
    } else if (mIsBeingUsedAsImage) {
      // To correctly unblock onload for a document that contains an SVG
      // image, we need to know when all of the SVG document's resources are
      // done loading, in a way comparable to |window.onload|. We fire this
      // event to indicate that the SVG should be considered fully loaded.
      // Because scripting is disabled on SVG-as-image documents, this event
      // is not accessible to content authors. (See bug 837135.)
      nsRefPtr<nsAsyncDOMEvent> e =
        new nsAsyncDOMEvent(this,
                            NS_LITERAL_STRING("MozSVGAsImageDocumentLoad"),
                            false,
                            false);
      e->PostDOMEvent();
    }
  }
}

class nsUnblockOnloadEvent : public nsRunnable {
public:
  nsUnblockOnloadEvent(nsDocument *doc) : mDoc(doc) {}
  NS_IMETHOD Run() {
    mDoc->DoUnblockOnload();
    return NS_OK;
  }
private:
  nsRefPtr<nsDocument> mDoc;
};

void
nsDocument::PostUnblockOnloadEvent()
{
  nsCOMPtr<nsIRunnable> evt = new nsUnblockOnloadEvent(this);
  nsresult rv = NS_DispatchToCurrentThread(evt);
  if (NS_SUCCEEDED(rv)) {
    // Stabilize block count so we don't post more events while this one is up
    ++mOnloadBlockCount;
  } else {
    NS_WARNING("failed to dispatch nsUnblockOnloadEvent");
  }
}

void
nsDocument::DoUnblockOnload()
{
  NS_PRECONDITION(!mDisplayDocument,
                  "Shouldn't get here for resource document");
  NS_PRECONDITION(mOnloadBlockCount != 0,
                  "Shouldn't have a count of zero here, since we stabilized in "
                  "PostUnblockOnloadEvent");

  --mOnloadBlockCount;

  if (mOnloadBlockCount != 0) {
    // We blocked again after the last unblock.  Nothing to do here.  We'll
    // post a new event when we unblock again.
    return;
  }

  if (mAsyncOnloadBlockCount != 0) {
    // We need to wait until the async onload block has been handled.
    PostUnblockOnloadEvent();
  }

  // If mScriptGlobalObject is null, we shouldn't be messing with the loadgroup
  // -- it's not ours.
  if (mScriptGlobalObject) {
    nsCOMPtr<nsILoadGroup> loadGroup = GetDocumentLoadGroup();
    if (loadGroup) {
      loadGroup->RemoveRequest(mOnloadBlocker, nullptr, NS_OK);
    }
  }
}

nsIContent*
nsDocument::GetContentInThisDocument(nsIFrame* aFrame) const
{
  for (nsIFrame* f = aFrame; f;
       f = nsLayoutUtils::GetParentOrPlaceholderForCrossDoc(f)) {
    nsIContent* content = f->GetContent();
    if (!content || content->IsInAnonymousSubtree())
      continue;

    if (content->OwnerDoc() == this) {
      return content;
    }
    // We must be in a subdocument so jump directly to the root frame.
    // GetParentOrPlaceholderForCrossDoc gets called immediately to jump up to
    // the containing document.
    f = f->PresContext()->GetPresShell()->GetRootFrame();
  }

  return nullptr;
}

void
nsDocument::DispatchPageTransition(EventTarget* aDispatchTarget,
                                   const nsAString& aType,
                                   bool aPersisted)
{
  if (aDispatchTarget) {
    nsCOMPtr<nsIDOMEvent> event;
    CreateEvent(NS_LITERAL_STRING("pagetransition"), getter_AddRefs(event));
    nsCOMPtr<nsIDOMPageTransitionEvent> ptEvent = do_QueryInterface(event);
    if (ptEvent && NS_SUCCEEDED(ptEvent->InitPageTransitionEvent(aType, true,
                                                                 true,
                                                                 aPersisted))) {
      event->SetTrusted(true);
      event->SetTarget(this);
      nsEventDispatcher::DispatchDOMEvent(aDispatchTarget, nullptr, event,
                                          nullptr, nullptr);
    }
  }
}

static bool
NotifyPageShow(nsIDocument* aDocument, void* aData)
{
  const bool* aPersistedPtr = static_cast<const bool*>(aData);
  aDocument->OnPageShow(*aPersistedPtr, nullptr);
  return true;
}

void
nsDocument::OnPageShow(bool aPersisted,
                       EventTarget* aDispatchStartTarget)
{
  mVisible = true;

  EnumerateFreezableElements(NotifyActivityChanged, nullptr);
  EnumerateExternalResources(NotifyPageShow, &aPersisted);

  Element* root = GetRootElement();
  if (aPersisted && root) {
    // Send out notifications that our <link> elements are attached.
    nsRefPtr<nsContentList> links = NS_GetContentList(root,
                                                      kNameSpaceID_Unknown,
                                                      NS_LITERAL_STRING("link"));

    uint32_t linkCount = links->Length(true);
    for (uint32_t i = 0; i < linkCount; ++i) {
      nsCOMPtr<nsILink> link = do_QueryInterface(links->Item(i, false));
      if (link) {
        link->LinkAdded();
      }
    }
  }

  // See nsIDocument
  if (!aDispatchStartTarget) {
    // Set mIsShowing before firing events, in case those event handlers
    // move us around.
    mIsShowing = true;
  }

  if (mAnimationController) {
    mAnimationController->OnPageShow();
  }

  if (aPersisted) {
    SetImagesNeedAnimating(true);
  }

  UpdateVisibilityState();

  nsCOMPtr<EventTarget> target = aDispatchStartTarget;
  if (!target) {
    target = do_QueryInterface(GetWindow());
  }
  DispatchPageTransition(target, NS_LITERAL_STRING("pageshow"), aPersisted);
}

static bool
NotifyPageHide(nsIDocument* aDocument, void* aData)
{
  const bool* aPersistedPtr = static_cast<const bool*>(aData);
  aDocument->OnPageHide(*aPersistedPtr, nullptr);
  return true;
}

static void
DispatchFullScreenChange(nsIDocument* aTarget)
{
  nsRefPtr<nsAsyncDOMEvent> e =
    new nsAsyncDOMEvent(aTarget,
                        NS_LITERAL_STRING("mozfullscreenchange"),
                        true,
                        false);
  e->PostDOMEvent();
}

void
nsDocument::OnPageHide(bool aPersisted,
                       EventTarget* aDispatchStartTarget)
{
  // Send out notifications that our <link> elements are detached,
  // but only if this is not a full unload.
  Element* root = GetRootElement();
  if (aPersisted && root) {
    nsRefPtr<nsContentList> links = NS_GetContentList(root,
                                                      kNameSpaceID_Unknown,
                                                      NS_LITERAL_STRING("link"));

    uint32_t linkCount = links->Length(true);
    for (uint32_t i = 0; i < linkCount; ++i) {
      nsCOMPtr<nsILink> link = do_QueryInterface(links->Item(i, false));
      if (link) {
        link->LinkRemoved();
      }
    }
  }

  // See nsIDocument
  if (!aDispatchStartTarget) {
    // Set mIsShowing before firing events, in case those event handlers
    // move us around.
    mIsShowing = false;
  }

  if (mAnimationController) {
    mAnimationController->OnPageHide();
  }

  if (aPersisted) {
    SetImagesNeedAnimating(false);
  }

  MozExitPointerLock();

  // Now send out a PageHide event.
  nsCOMPtr<EventTarget> target = aDispatchStartTarget;
  if (!target) {
    target = do_QueryInterface(GetWindow());
  }
  DispatchPageTransition(target, NS_LITERAL_STRING("pagehide"), aPersisted);

  mVisible = false;

  UpdateVisibilityState();

  EnumerateExternalResources(NotifyPageHide, &aPersisted);
  EnumerateFreezableElements(NotifyActivityChanged, nullptr);

  if (IsFullScreenDoc()) {
    // If this document was fullscreen, we should exit fullscreen in this
    // doctree branch. This ensures that if the user navigates while in
    // fullscreen mode we don't leave its still visible ancestor documents
    // in fullscreen mode. So exit fullscreen in the document's fullscreen
    // root document, as this will exit fullscreen in all the root's
    // descendant documents. Note that documents are removed from the
    // doctree by the time OnPageHide() is called, so we must store a
    // reference to the root (in nsDocument::mFullscreenRoot) since we can't
    // just traverse the doctree to get the root.
    nsIDocument::ExitFullscreen(this, /* async */ false);

    // Since the document is removed from the doctree before OnPageHide() is
    // called, ExitFullscreen() can't traverse from the root down to *this*
    // document, so we must manually call CleanupFullscreenState() below too.
    // Note that CleanupFullscreenState() clears nsDocument::mFullscreenRoot,
    // so we *must* call it after ExitFullscreen(), not before.
    // OnPageHide() is called in every hidden (i.e. descendant) document,
    // so calling CleanupFullscreenState() here will ensure all hidden
    // documents have their fullscreen state reset.
    CleanupFullscreenState();

    // If anyone was listening to this document's state, advertizing the state
    // change would be the least of the politeness.
    DispatchFullScreenChange(this);
  }
}

void
nsDocument::WillDispatchMutationEvent(nsINode* aTarget)
{
  NS_ASSERTION(mSubtreeModifiedDepth != 0 ||
               mSubtreeModifiedTargets.Count() == 0,
               "mSubtreeModifiedTargets not cleared after dispatching?");
  ++mSubtreeModifiedDepth;
  if (aTarget) {
    // MayDispatchMutationEvent is often called just before this method,
    // so it has already appended the node to mSubtreeModifiedTargets.
    int32_t count = mSubtreeModifiedTargets.Count();
    if (!count || mSubtreeModifiedTargets[count - 1] != aTarget) {
      mSubtreeModifiedTargets.AppendObject(aTarget);
    }
  }
}

void
nsDocument::MutationEventDispatched(nsINode* aTarget)
{
  --mSubtreeModifiedDepth;
  if (mSubtreeModifiedDepth == 0) {
    int32_t count = mSubtreeModifiedTargets.Count();
    if (!count) {
      return;
    }

    nsCOMPtr<nsPIDOMWindow> window;
    window = do_QueryInterface(GetWindow());
    if (window &&
        !window->HasMutationListeners(NS_EVENT_BITS_MUTATION_SUBTREEMODIFIED)) {
      mSubtreeModifiedTargets.Clear();
      return;
    }

    nsCOMArray<nsINode> realTargets;
    for (int32_t i = 0; i < count; ++i) {
      nsINode* possibleTarget = mSubtreeModifiedTargets[i];
      nsCOMPtr<nsIContent> content = do_QueryInterface(possibleTarget);
      if (content && content->ChromeOnlyAccess()) {
        continue;
      }

      nsINode* commonAncestor = nullptr;
      int32_t realTargetCount = realTargets.Count();
      for (int32_t j = 0; j < realTargetCount; ++j) {
        commonAncestor =
          nsContentUtils::GetCommonAncestor(possibleTarget, realTargets[j]);
        if (commonAncestor) {
          realTargets.ReplaceObjectAt(commonAncestor, j);
          break;
        }
      }
      if (!commonAncestor) {
        realTargets.AppendObject(possibleTarget);
      }
    }

    mSubtreeModifiedTargets.Clear();

    int32_t realTargetCount = realTargets.Count();
    for (int32_t k = 0; k < realTargetCount; ++k) {
      nsMutationEvent mutation(true, NS_MUTATION_SUBTREEMODIFIED);
      (new nsAsyncDOMEvent(realTargets[k], mutation))->RunDOMEventWhenSafe();
    }
  }
}

void
nsDocument::AddStyleRelevantLink(Link* aLink)
{
  NS_ASSERTION(aLink, "Passing in a null link.  Expect crashes RSN!");
#ifdef DEBUG
  nsPtrHashKey<Link>* entry = mStyledLinks.GetEntry(aLink);
  NS_ASSERTION(!entry, "Document already knows about this Link!");
  mStyledLinksCleared = false;
#endif
  (void)mStyledLinks.PutEntry(aLink);
}

void
nsDocument::ForgetLink(Link* aLink)
{
  NS_ASSERTION(aLink, "Passing in a null link.  Expect crashes RSN!");
#ifdef DEBUG
  nsPtrHashKey<Link>* entry = mStyledLinks.GetEntry(aLink);
  NS_ASSERTION(entry || mStyledLinksCleared,
               "Document knows nothing about this Link!");
#endif
  (void)mStyledLinks.RemoveEntry(aLink);
}

void
nsDocument::DestroyElementMaps()
{
#ifdef DEBUG
  mStyledLinksCleared = true;
#endif
  mStyledLinks.Clear();
  mIdentifierMap.Clear();
  ++mExpandoAndGeneration.generation;
}

static
PLDHashOperator
EnumerateStyledLinks(nsPtrHashKey<Link>* aEntry, void* aArray)
{
  LinkArray* array = static_cast<LinkArray*>(aArray);
  (void)array->AppendElement(aEntry->GetKey());
  return PL_DHASH_NEXT;
}

void
nsDocument::RefreshLinkHrefs()
{
  // Get a list of all links we know about.  We will reset them, which will
  // remove them from the document, so we need a copy of what is in the
  // hashtable.
  LinkArray linksToNotify(mStyledLinks.Count());
  (void)mStyledLinks.EnumerateEntries(EnumerateStyledLinks, &linksToNotify);

  // Reset all of our styled links.
  nsAutoScriptBlocker scriptBlocker;
  for (LinkArray::size_type i = 0; i < linksToNotify.Length(); i++) {
    linksToNotify[i]->ResetLinkState(true, linksToNotify[i]->ElementHasHref());
  }
}

nsresult
nsDocument::CloneDocHelper(nsDocument* clone) const
{
  clone->mIsStaticDocument = mCreatingStaticClone;

  // Init document
  nsresult rv = clone->Init();
  NS_ENSURE_SUCCESS(rv, rv);

  // Set URI/principal
  clone->nsDocument::SetDocumentURI(nsIDocument::GetDocumentURI());
  // Must set the principal first, since SetBaseURI checks it.
  clone->SetPrincipal(NodePrincipal());
  clone->mDocumentBaseURI = mDocumentBaseURI;

  if (mCreatingStaticClone) {
    nsCOMPtr<nsILoadGroup> loadGroup;

    // |mDocumentContainer| is the container of the document that is being
    // created and not the original container. See CreateStaticClone function().
    nsCOMPtr<nsIDocumentLoader> docLoader = do_QueryReferent(mDocumentContainer);
    if (docLoader) {
      docLoader->GetLoadGroup(getter_AddRefs(loadGroup));
    }
    nsCOMPtr<nsIChannel> channel = GetChannel();
    if (channel && loadGroup) {
      clone->Reset(channel, loadGroup);
    } else {
      nsIURI* uri = static_cast<const nsIDocument*>(this)->GetDocumentURI();
      if (uri) {
        clone->ResetToURI(uri, loadGroup, NodePrincipal());
      }
    }
    nsCOMPtr<nsISupports> container = GetContainer();
    clone->SetContainer(container);
  }

  // Set scripting object
  bool hasHadScriptObject = true;
  nsIScriptGlobalObject* scriptObject =
    GetScriptHandlingObject(hasHadScriptObject);
  NS_ENSURE_STATE(scriptObject || !hasHadScriptObject);
  if (scriptObject) {
    clone->SetScriptHandlingObject(scriptObject);
  } else {
    clone->SetScopeObject(GetScopeObject());
  }
  // Make the clone a data document
  clone->SetLoadedAsData(true);

  // Misc state

  // State from nsIDocument
  clone->mCharacterSet = mCharacterSet;
  clone->mCharacterSetSource = mCharacterSetSource;
  clone->mCompatMode = mCompatMode;
  clone->mBidiOptions = mBidiOptions;
  clone->mContentLanguage = mContentLanguage;
  clone->SetContentTypeInternal(GetContentTypeInternal());
  clone->mSecurityInfo = mSecurityInfo;

  // State from nsDocument
  clone->mIsRegularHTML = mIsRegularHTML;
  clone->mXMLDeclarationBits = mXMLDeclarationBits;
  clone->mBaseTarget = mBaseTarget;
  return NS_OK;
}

void
nsDocument::SetReadyStateInternal(ReadyState rs)
{
  mReadyState = rs;
  if (rs == READYSTATE_UNINITIALIZED) {
    // Transition back to uninitialized happens only to keep assertions happy
    // right before readyState transitions to something else. Make this
    // transition undetectable by Web content.
    return;
  }
  if (mTiming) {
    switch (rs) {
      case READYSTATE_LOADING:
        mTiming->NotifyDOMLoading(nsIDocument::GetDocumentURI());
        break;
      case READYSTATE_INTERACTIVE:
        mTiming->NotifyDOMInteractive(nsIDocument::GetDocumentURI());
        break;
      case READYSTATE_COMPLETE:
        mTiming->NotifyDOMComplete(nsIDocument::GetDocumentURI());
        break;
      default:
        NS_WARNING("Unexpected ReadyState value");
        break;
    }
  }
  // At the time of loading start, we don't have timing object, record time.
  if (READYSTATE_LOADING == rs) {
    mLoadingTimeStamp = mozilla::TimeStamp::Now();
  }

  nsRefPtr<nsAsyncDOMEvent> plevent =
    new nsAsyncDOMEvent(this, NS_LITERAL_STRING("readystatechange"), false, false);
  if (plevent) {
    plevent->RunDOMEventWhenSafe();
  }
}

NS_IMETHODIMP
nsDocument::GetReadyState(nsAString& aReadyState)
{
  nsIDocument::GetReadyState(aReadyState);
  return NS_OK;
}

void
nsIDocument::GetReadyState(nsAString& aReadyState) const
{
  switch(mReadyState) {
  case READYSTATE_LOADING :
    aReadyState.Assign(NS_LITERAL_STRING("loading"));
    break;
  case READYSTATE_INTERACTIVE :
    aReadyState.Assign(NS_LITERAL_STRING("interactive"));
    break;
  case READYSTATE_COMPLETE :
    aReadyState.Assign(NS_LITERAL_STRING("complete"));
    break;
  default:
    aReadyState.Assign(NS_LITERAL_STRING("uninitialized"));
  }
}

static bool
SuppressEventHandlingInDocument(nsIDocument* aDocument, void* aData)
{
  aDocument->SuppressEventHandling(*static_cast<uint32_t*>(aData));
  return true;
}

void
nsDocument::SuppressEventHandling(uint32_t aIncrease)
{
  if (mEventsSuppressed == 0 && aIncrease != 0 && mPresShell &&
      mScriptGlobalObject) {
    RevokeAnimationFrameNotifications();
  }
  mEventsSuppressed += aIncrease;
  EnumerateSubDocuments(SuppressEventHandlingInDocument, &aIncrease);
}

static void
FireOrClearDelayedEvents(nsTArray<nsCOMPtr<nsIDocument> >& aDocuments,
                         bool aFireEvents)
{
  nsIFocusManager* fm = nsFocusManager::GetFocusManager();
  if (!fm)
    return;

  for (uint32_t i = 0; i < aDocuments.Length(); ++i) {
    if (!aDocuments[i]->EventHandlingSuppressed()) {
      fm->FireDelayedEvents(aDocuments[i]);
      nsCOMPtr<nsIPresShell> shell = aDocuments[i]->GetShell();
      if (shell) {
        shell->FireOrClearDelayedEvents(aFireEvents);
      }
    }
  }
}

void
nsDocument::MaybePreLoadImage(nsIURI* uri, const nsAString &aCrossOriginAttr)
{
  // Early exit if the img is already present in the img-cache
  // which indicates that the "real" load has already started and
  // that we shouldn't preload it.
  int16_t blockingStatus;
  if (nsContentUtils::IsImageInCache(uri, static_cast<nsIDocument *>(this)) ||
      !nsContentUtils::CanLoadImage(uri, static_cast<nsIDocument *>(this),
                                    this, NodePrincipal(), &blockingStatus)) {
    return;
  }

  nsLoadFlags loadFlags = nsIRequest::LOAD_NORMAL;
  switch (Element::StringToCORSMode(aCrossOriginAttr)) {
  case CORS_NONE:
    // Nothing to do
    break;
  case CORS_ANONYMOUS:
    loadFlags |= imgILoader::LOAD_CORS_ANONYMOUS;
    break;
  case CORS_USE_CREDENTIALS:
    loadFlags |= imgILoader::LOAD_CORS_USE_CREDENTIALS;
    break;
  default:
    MOZ_CRASH("Unknown CORS mode!");
  }

  // Image not in cache - trigger preload
  nsRefPtr<imgRequestProxy> request;
  nsresult rv =
    nsContentUtils::LoadImage(uri,
                              this,
                              NodePrincipal(),
                              mDocumentURI, // uri of document used as referrer
                              nullptr,       // no observer
                              loadFlags,
                              getter_AddRefs(request));

  // Pin image-reference to avoid evicting it from the img-cache before
  // the "real" load occurs. Unpinned in DispatchContentLoadedEvents and
  // unlink
  if (NS_SUCCEEDED(rv)) {
    mPreloadingImages.AppendObject(request);
  }
}

nsEventStates
nsDocument::GetDocumentState()
{
  if (!mGotDocumentState.HasState(NS_DOCUMENT_STATE_RTL_LOCALE)) {
    if (IsDocumentRightToLeft()) {
      mDocumentState |= NS_DOCUMENT_STATE_RTL_LOCALE;
    }
    mGotDocumentState |= NS_DOCUMENT_STATE_RTL_LOCALE;
  }
  if (!mGotDocumentState.HasState(NS_DOCUMENT_STATE_WINDOW_INACTIVE)) {
    nsIPresShell* shell = GetShell();
    if (shell && shell->GetPresContext() &&
        shell->GetPresContext()->IsTopLevelWindowInactive()) {
      mDocumentState |= NS_DOCUMENT_STATE_WINDOW_INACTIVE;
    }
    mGotDocumentState |= NS_DOCUMENT_STATE_WINDOW_INACTIVE;
  }
  return mDocumentState;
}

namespace {

/**
 * Stub for LoadSheet(), since all we want is to get the sheet into
 * the CSSLoader's style cache
 */
class StubCSSLoaderObserver MOZ_FINAL : public nsICSSLoaderObserver {
public:
  NS_IMETHOD
  StyleSheetLoaded(nsCSSStyleSheet*, bool, nsresult)
  {
    return NS_OK;
  }
  NS_DECL_ISUPPORTS
};
NS_IMPL_ISUPPORTS1(StubCSSLoaderObserver, nsICSSLoaderObserver)

}

void
nsDocument::PreloadStyle(nsIURI* uri, const nsAString& charset,
                         const nsAString& aCrossOriginAttr)
{
  // The CSSLoader will retain this object after we return.
  nsCOMPtr<nsICSSLoaderObserver> obs = new StubCSSLoaderObserver();

  // Charset names are always ASCII.
  CSSLoader()->LoadSheet(uri, NodePrincipal(),
                         NS_LossyConvertUTF16toASCII(charset),
                         obs,
                         Element::StringToCORSMode(aCrossOriginAttr));
}

nsresult
nsDocument::LoadChromeSheetSync(nsIURI* uri, bool isAgentSheet,
                                nsCSSStyleSheet** sheet)
{
  return CSSLoader()->LoadSheetSync(uri, isAgentSheet, isAgentSheet, sheet);
}

class nsDelayedEventDispatcher : public nsRunnable
{
public:
  nsDelayedEventDispatcher(nsTArray<nsCOMPtr<nsIDocument> >& aDocuments)
  {
    mDocuments.SwapElements(aDocuments);
  }
  virtual ~nsDelayedEventDispatcher() {}

  NS_IMETHOD Run()
  {
    FireOrClearDelayedEvents(mDocuments, true);
    return NS_OK;
  }

private:
  nsTArray<nsCOMPtr<nsIDocument> > mDocuments;
};

static bool
GetAndUnsuppressSubDocuments(nsIDocument* aDocument, void* aData)
{
  uint32_t suppression = aDocument->EventHandlingSuppressed();
  if (suppression > 0) {
    static_cast<nsDocument*>(aDocument)->DecreaseEventSuppression();
  }
  nsTArray<nsCOMPtr<nsIDocument> >* docs =
    static_cast<nsTArray<nsCOMPtr<nsIDocument> >* >(aData);
  docs->AppendElement(aDocument);
  aDocument->EnumerateSubDocuments(GetAndUnsuppressSubDocuments, docs);
  return true;
}

void
nsDocument::UnsuppressEventHandlingAndFireEvents(bool aFireEvents)
{
  nsTArray<nsCOMPtr<nsIDocument> > documents;
  GetAndUnsuppressSubDocuments(this, &documents);

  if (aFireEvents) {
    NS_DispatchToCurrentThread(new nsDelayedEventDispatcher(documents));
  } else {
    FireOrClearDelayedEvents(documents, false);
  }
}

nsISupports*
nsDocument::GetCurrentContentSink()
{
  return mParser ? mParser->GetContentSink() : nullptr;
}

nsIDocument*
nsDocument::GetTemplateContentsOwner()
{
  if (!mTemplateContentsOwner) {
    bool hasHadScriptObject = true;
    nsIScriptGlobalObject* scriptObject =
      GetScriptHandlingObject(hasHadScriptObject);
    NS_ENSURE_TRUE(scriptObject || !hasHadScriptObject, nullptr);

    nsCOMPtr<nsIDOMDocument> domDocument;
    nsresult rv = NS_NewDOMDocument(getter_AddRefs(domDocument),
                                    EmptyString(), // aNamespaceURI
                                    EmptyString(), // aQualifiedName
                                    nullptr, // aDoctype
                                    nsIDocument::GetDocumentURI(),
                                    nsIDocument::GetDocBaseURI(),
                                    NodePrincipal(),
                                    true, // aLoadedAsData
                                    scriptObject, // aEventObject
                                    DocumentFlavorHTML);
    NS_ENSURE_SUCCESS(rv, nullptr);

    mTemplateContentsOwner = do_QueryInterface(domDocument);
    NS_ENSURE_TRUE(mTemplateContentsOwner, nullptr);

    mTemplateContentsOwner->SetScriptHandlingObject(scriptObject);
  }

  return mTemplateContentsOwner;
}

void
nsDocument::RegisterHostObjectUri(const nsACString& aUri)
{
  mHostObjectURIs.AppendElement(aUri);
}

void
nsDocument::UnregisterHostObjectUri(const nsACString& aUri)
{
  mHostObjectURIs.RemoveElement(aUri);
}

void
nsDocument::SetScrollToRef(nsIURI *aDocumentURI)
{
  if (!aDocumentURI) {
    return;
  }

  nsAutoCString ref;

  // Since all URI's that pass through here aren't URL's we can't
  // rely on the nsIURI implementation for providing a way for
  // finding the 'ref' part of the URI, we'll haveto revert to
  // string routines for finding the data past '#'

  aDocumentURI->GetSpec(ref);

  nsReadingIterator<char> start, end;

  ref.BeginReading(start);
  ref.EndReading(end);

  if (FindCharInReadable('#', start, end)) {
    ++start; // Skip over the '#'

    mScrollToRef = Substring(start, end);
  }
}

void
nsDocument::ScrollToRef()
{
  if (mScrolledToRefAlready) {
    return;
  }

  if (mScrollToRef.IsEmpty()) {
    return;
  }

  char* tmpstr = ToNewCString(mScrollToRef);
  if (!tmpstr) {
    return;
  }

  nsUnescape(tmpstr);
  nsAutoCString unescapedRef;
  unescapedRef.Assign(tmpstr);
  nsMemory::Free(tmpstr);

  nsresult rv = NS_ERROR_FAILURE;
  // We assume that the bytes are in UTF-8, as it says in the spec:
  // http://www.w3.org/TR/html4/appendix/notes.html#h-B.2.1
  NS_ConvertUTF8toUTF16 ref(unescapedRef);

  nsCOMPtr<nsIPresShell> shell = GetShell();
  if (shell) {
    // Check an empty string which might be caused by the UTF-8 conversion
    if (!ref.IsEmpty()) {
      // Note that GoToAnchor will handle flushing layout as needed.
      rv = shell->GoToAnchor(ref, mChangeScrollPosWhenScrollingToRef);
    } else {
      rv = NS_ERROR_FAILURE;
    }

    // If UTF-8 URI failed then try to assume the string as a
    // document's charset.

    if (NS_FAILED(rv)) {
      const nsACString &docCharset = GetDocumentCharacterSet();

      rv = nsContentUtils::ConvertStringFromCharset(docCharset, unescapedRef, ref);

      if (NS_SUCCEEDED(rv) && !ref.IsEmpty()) {
        rv = shell->GoToAnchor(ref, mChangeScrollPosWhenScrollingToRef);
      }
    }
    if (NS_SUCCEEDED(rv)) {
      mScrolledToRefAlready = true;
    }
  }
}

void
nsDocument::ResetScrolledToRefAlready()
{
  mScrolledToRefAlready = false;
}

void
nsDocument::SetChangeScrollPosWhenScrollingToRef(bool aValue)
{
  mChangeScrollPosWhenScrollingToRef = aValue;
}

void
nsIDocument::RegisterFreezableElement(nsIContent* aContent)
{
  if (!mFreezableElements) {
    mFreezableElements = new nsTHashtable<nsPtrHashKey<nsIContent> >();
    if (!mFreezableElements)
      return;
    mFreezableElements->Init();
  }
  mFreezableElements->PutEntry(aContent);
}

bool
nsIDocument::UnregisterFreezableElement(nsIContent* aContent)
{
  if (!mFreezableElements)
    return false;
  if (!mFreezableElements->GetEntry(aContent))
    return false;
  mFreezableElements->RemoveEntry(aContent);
  return true;
}

struct EnumerateFreezablesData {
  nsIDocument::FreezableElementEnumerator mEnumerator;
  void* mData;
};

static PLDHashOperator
EnumerateFreezables(nsPtrHashKey<nsIContent>* aEntry, void* aData)
{
  EnumerateFreezablesData* data = static_cast<EnumerateFreezablesData*>(aData);
  data->mEnumerator(aEntry->GetKey(), data->mData);
  return PL_DHASH_NEXT;
}

void
nsIDocument::EnumerateFreezableElements(FreezableElementEnumerator aEnumerator,
                                        void* aData)
{
  if (!mFreezableElements)
    return;
  EnumerateFreezablesData data = { aEnumerator, aData };
  mFreezableElements->EnumerateEntries(EnumerateFreezables, &data);
}

void
nsIDocument::RegisterPendingLinkUpdate(Link* aLink)
{
  mLinksToUpdate.PutEntry(aLink);
  mHasLinksToUpdate = true;
}

void
nsIDocument::UnregisterPendingLinkUpdate(Link* aLink)
{
  if (!mHasLinksToUpdate)
    return;

  mLinksToUpdate.RemoveEntry(aLink);
}

static PLDHashOperator
EnumeratePendingLinkUpdates(nsPtrHashKey<Link>* aEntry, void* aData)
{
  aEntry->GetKey()->GetElement()->UpdateLinkState(aEntry->GetKey()->LinkState());
  return PL_DHASH_NEXT;
}

void
nsIDocument::FlushPendingLinkUpdates()
{
  if (!mHasLinksToUpdate)
    return;

  nsAutoScriptBlocker scriptBlocker;
  mLinksToUpdate.EnumerateEntries(EnumeratePendingLinkUpdates, nullptr);
  mLinksToUpdate.Clear();
  mHasLinksToUpdate = false;
}

already_AddRefed<nsIDocument>
nsIDocument::CreateStaticClone(nsISupports* aCloneContainer)
{
  nsCOMPtr<nsIDOMDocument> domDoc = do_QueryInterface(this);
  NS_ENSURE_TRUE(domDoc, nullptr);
  mCreatingStaticClone = true;

  // Make document use different container during cloning.
  nsCOMPtr<nsISupports> originalContainer = GetContainer();
  SetContainer(aCloneContainer);
  nsCOMPtr<nsIDOMNode> clonedNode;
  nsresult rv = domDoc->CloneNode(true, 1, getter_AddRefs(clonedNode));
  SetContainer(originalContainer);

  nsCOMPtr<nsIDocument> clonedDoc;
  if (NS_SUCCEEDED(rv)) {
    clonedDoc = do_QueryInterface(clonedNode);
    if (clonedDoc) {
      if (IsStaticDocument()) {
        clonedDoc->mOriginalDocument = mOriginalDocument;
      } else {
        clonedDoc->mOriginalDocument = this;
      }
      int32_t sheetsCount = GetNumberOfStyleSheets();
      for (int32_t i = 0; i < sheetsCount; ++i) {
        nsRefPtr<nsCSSStyleSheet> sheet = do_QueryObject(GetStyleSheetAt(i));
        if (sheet) {
          if (sheet->IsApplicable()) {
            nsRefPtr<nsCSSStyleSheet> clonedSheet =
              sheet->Clone(nullptr, nullptr, clonedDoc, nullptr);
            NS_WARN_IF_FALSE(clonedSheet, "Cloning a stylesheet didn't work!");
            if (clonedSheet) {
              clonedDoc->AddStyleSheet(clonedSheet);
            }
          }
        }
      }

      sheetsCount = GetNumberOfCatalogStyleSheets();
      for (int32_t i = 0; i < sheetsCount; ++i) {
        nsRefPtr<nsCSSStyleSheet> sheet =
          do_QueryObject(GetCatalogStyleSheetAt(i));
        if (sheet) {
          if (sheet->IsApplicable()) {
            nsRefPtr<nsCSSStyleSheet> clonedSheet =
              sheet->Clone(nullptr, nullptr, clonedDoc, nullptr);
            NS_WARN_IF_FALSE(clonedSheet, "Cloning a stylesheet didn't work!");
            if (clonedSheet) {
              clonedDoc->AddCatalogStyleSheet(clonedSheet);
            }
          }
        }
      }
    }
  }
  mCreatingStaticClone = false;
  return clonedDoc.forget();
}

nsresult
nsIDocument::ScheduleFrameRequestCallback(const FrameRequestCallbackHolder& aCallback,
                                          int32_t *aHandle)
{
  if (mFrameRequestCallbackCounter == INT32_MAX) {
    // Can't increment without overflowing; bail out
    return NS_ERROR_NOT_AVAILABLE;
  }
  int32_t newHandle = ++mFrameRequestCallbackCounter;

  bool alreadyRegistered = !mFrameRequestCallbacks.IsEmpty();
  DebugOnly<FrameRequest*> request =
    mFrameRequestCallbacks.AppendElement(FrameRequest(aCallback, newHandle));
  NS_ASSERTION(request, "This is supposed to be infallible!");
  if (!alreadyRegistered && mPresShell && IsEventHandlingEnabled()) {
    mPresShell->GetPresContext()->RefreshDriver()->
      ScheduleFrameRequestCallbacks(this);
  }

  *aHandle = newHandle;
  return NS_OK;
}

void
nsIDocument::CancelFrameRequestCallback(int32_t aHandle)
{
  // mFrameRequestCallbacks is stored sorted by handle
  if (mFrameRequestCallbacks.RemoveElementSorted(aHandle) &&
      mFrameRequestCallbacks.IsEmpty() &&
      mPresShell && IsEventHandlingEnabled()) {
    mPresShell->GetPresContext()->RefreshDriver()->
      RevokeFrameRequestCallbacks(this);
  }
}

nsresult
nsDocument::GetStateObject(nsIVariant** aState)
{
  // Get the document's current state object. This is the object backing both
  // history.state and popStateEvent.state.
  //
  // mStateObjectContainer may be null; this just means that there's no
  // current state object.

  nsCOMPtr<nsIVariant> stateObj;
  if (!mStateObjectCached && mStateObjectContainer) {
    AutoPushJSContext cx(nsContentUtils::GetContextFromDocument(this));
    mStateObjectContainer->
      DeserializeToVariant(cx, getter_AddRefs(mStateObjectCached));
  }

  NS_IF_ADDREF(*aState = mStateObjectCached);

  return NS_OK;
}

nsDOMNavigationTiming*
nsDocument::GetNavigationTiming() const
{
  return mTiming;
}

nsresult
nsDocument::SetNavigationTiming(nsDOMNavigationTiming* aTiming)
{
  mTiming = aTiming;
  if (!mLoadingTimeStamp.IsNull() && mTiming) {
    mTiming->SetDOMLoadingTimeStamp(nsIDocument::GetDocumentURI(), mLoadingTimeStamp);
  }
  return NS_OK;
}

Element*
nsDocument::FindImageMap(const nsAString& aUseMapValue)
{
  if (aUseMapValue.IsEmpty()) {
    return nullptr;
  }

  nsAString::const_iterator start, end;
  aUseMapValue.BeginReading(start);
  aUseMapValue.EndReading(end);

  int32_t hash = aUseMapValue.FindChar('#');
  if (hash < 0) {
    return nullptr;
  }
  // aUsemap contains a '#', set start to point right after the '#'
  start.advance(hash + 1);

  if (start == end) {
    return nullptr; // aUsemap == "#"
  }

  const nsAString& mapName = Substring(start, end);

  if (!mImageMaps) {
    mImageMaps = new nsContentList(this, kNameSpaceID_XHTML, nsGkAtoms::map, nsGkAtoms::map);
  }

  uint32_t i, n = mImageMaps->Length(true);
  nsString name;
  for (i = 0; i < n; ++i) {
    nsIContent* map = mImageMaps->Item(i);
    if (map->AttrValueIs(kNameSpaceID_None, nsGkAtoms::id, mapName,
                         eCaseMatters) ||
        (map->GetAttr(kNameSpaceID_None, nsGkAtoms::name, name) &&
         mapName.Equals(name, nsCaseInsensitiveStringComparator()))) {
      return map->AsElement();
    }
  }

  return nullptr;
}

#define DEPRECATED_OPERATION(_op) #_op "Warning",
static const char* kWarnings[] = {
#include "nsDeprecatedOperationList.h"
  nullptr
};
#undef DEPRECATED_OPERATION

void
nsIDocument::WarnOnceAbout(DeprecatedOperations aOperation,
                           bool asError /* = false */)
{
  PR_STATIC_ASSERT(eDeprecatedOperationCount <= 64);
  if (mWarnedAbout & (1ull << aOperation)) {
    return;
  }
  mWarnedAbout |= (1ull << aOperation);
  uint32_t flags = asError ? nsIScriptError::errorFlag
                           : nsIScriptError::warningFlag;
  nsContentUtils::ReportToConsole(flags,
                                  "DOM Core", this,
                                  nsContentUtils::eDOM_PROPERTIES,
                                  kWarnings[aOperation]);
}

nsresult
nsDocument::AddImage(imgIRequest* aImage)
{
  NS_ENSURE_ARG_POINTER(aImage);

  // See if the image is already in the hashtable. If it is, get the old count.
  uint32_t oldCount = 0;
  mImageTracker.Get(aImage, &oldCount);

  // Put the image in the hashtable, with the proper count.
  mImageTracker.Put(aImage, oldCount + 1);

  nsresult rv = NS_OK;

  // If this is the first insertion and we're locking images, lock this image
  // too.
  if (oldCount == 0) {
    if (mLockingImages)
      rv = aImage->LockImage();
    if (NS_SUCCEEDED(rv) && (!sOnloadDecodeLimit ||
                             mImageTracker.Count() < sOnloadDecodeLimit))
      rv = aImage->StartDecoding();
  }

  // If this is the first insertion and we're animating images, request
  // that this image be animated too.
  if (oldCount == 0 && mAnimatingImages) {
    nsresult rv2 = aImage->IncrementAnimationConsumers();
    rv = NS_SUCCEEDED(rv) ? rv2 : rv;
  }

  return rv;
}

static void
NotifyAudioAvailableListener(nsIContent *aContent, void *aUnused)
{
  nsCOMPtr<nsIDOMHTMLMediaElement> domMediaElem(do_QueryInterface(aContent));
  if (domMediaElem) {
    HTMLMediaElement* mediaElem = static_cast<HTMLMediaElement*>(aContent);
    mediaElem->NotifyAudioAvailableListener();
  }
}

void
nsDocument::NotifyAudioAvailableListener()
{
  mHasAudioAvailableListener = true;
  EnumerateFreezableElements(::NotifyAudioAvailableListener, nullptr);
}

nsresult
nsDocument::RemoveImage(imgIRequest* aImage, uint32_t aFlags)
{
  NS_ENSURE_ARG_POINTER(aImage);

  // Get the old count. It should exist and be > 0.
  uint32_t count = 0;
  DebugOnly<bool> found = mImageTracker.Get(aImage, &count);
  NS_ABORT_IF_FALSE(found, "Removing image that wasn't in the tracker!");
  NS_ABORT_IF_FALSE(count > 0, "Entry in the cache tracker with count 0!");

  // We're removing, so decrement the count.
  count--;

  // If the count is now zero, remove from the tracker.
  // Otherwise, set the new value.
  if (count != 0) {
    mImageTracker.Put(aImage, count);
    return NS_OK;
  }

  mImageTracker.Remove(aImage);

  nsresult rv = NS_OK;

  // Now that we're no longer tracking this image, unlock it if we'd
  // previously locked it.
  if (mLockingImages) {
    rv = aImage->UnlockImage();
  }

  // If we're animating images, remove our request to animate this one.
  if (mAnimatingImages) {
    nsresult rv2 = aImage->DecrementAnimationConsumers();
    rv = NS_SUCCEEDED(rv) ? rv2 : rv;
  }

  if (aFlags & REQUEST_DISCARD) {
    // Request that the image be discarded if nobody else holds a lock on it.
    // Do this even if !mLockingImages, because even if we didn't just unlock
    // this image, it might still be a candidate for discarding.
    aImage->RequestDiscard();
  }

  return rv;
}

nsresult
nsDocument::AddPlugin(nsIObjectLoadingContent* aPlugin)
{
  MOZ_ASSERT(aPlugin);
  if (!mPlugins.PutEntry(aPlugin)) {
    return NS_ERROR_OUT_OF_MEMORY;
  }
  return NS_OK;
}

void
nsDocument::RemovePlugin(nsIObjectLoadingContent* aPlugin)
{
  MOZ_ASSERT(aPlugin);
  mPlugins.RemoveEntry(aPlugin);
}

static bool
AllSubDocumentPluginEnum(nsIDocument* aDocument, void* userArg)
{
  nsTArray<nsIObjectLoadingContent*>* plugins =
    reinterpret_cast< nsTArray<nsIObjectLoadingContent*>* >(userArg);
  MOZ_ASSERT(plugins);
  aDocument->GetPlugins(*plugins);
  return true;
}

static PLDHashOperator
AllPluginEnum(nsPtrHashKey<nsIObjectLoadingContent>* aPlugin, void* userArg)
{
  nsTArray<nsIObjectLoadingContent*>* allPlugins =
    reinterpret_cast< nsTArray<nsIObjectLoadingContent*>* >(userArg);
  MOZ_ASSERT(allPlugins);
  allPlugins->AppendElement(aPlugin->GetKey());
  return PL_DHASH_NEXT;
}

void
nsDocument::GetPlugins(nsTArray<nsIObjectLoadingContent*>& aPlugins)
{
  aPlugins.SetCapacity(aPlugins.Length() + mPlugins.Count());
  mPlugins.EnumerateEntries(AllPluginEnum, &aPlugins);
  EnumerateSubDocuments(AllSubDocumentPluginEnum, &aPlugins);
}

PLDHashOperator LockEnumerator(imgIRequest* aKey,
                               uint32_t aData,
                               void*    userArg)
{
  aKey->LockImage();
  aKey->RequestDecode();
  return PL_DHASH_NEXT;
}

PLDHashOperator UnlockEnumerator(imgIRequest* aKey,
                                 uint32_t aData,
                                 void*    userArg)
{
  aKey->UnlockImage();
  return PL_DHASH_NEXT;
}


nsresult
nsDocument::SetImageLockingState(bool aLocked)
{
  if (XRE_GetProcessType() == GeckoProcessType_Content &&
      !Preferences::GetBool("content.image.allow_locking", true)) {
    return NS_OK;
  }

  // If there's no change, there's nothing to do.
  if (mLockingImages == aLocked)
    return NS_OK;

  // Otherwise, iterate over our images and perform the appropriate action.
  mImageTracker.EnumerateRead(aLocked ? LockEnumerator
                                      : UnlockEnumerator,
                              nullptr);

  // Update state.
  mLockingImages = aLocked;

  return NS_OK;
}

PLDHashOperator IncrementAnimationEnumerator(imgIRequest* aKey,
                                             uint32_t aData,
                                             void*    userArg)
{
  aKey->IncrementAnimationConsumers();
  return PL_DHASH_NEXT;
}

PLDHashOperator DecrementAnimationEnumerator(imgIRequest* aKey,
                                             uint32_t aData,
                                             void*    userArg)
{
  aKey->DecrementAnimationConsumers();
  return PL_DHASH_NEXT;
}

void
nsDocument::SetImagesNeedAnimating(bool aAnimating)
{
  // If there's no change, there's nothing to do.
  if (mAnimatingImages == aAnimating)
    return;

  // Otherwise, iterate over our images and perform the appropriate action.
  mImageTracker.EnumerateRead(aAnimating ? IncrementAnimationEnumerator
                                         : DecrementAnimationEnumerator,
                              nullptr);

  // Update state.
  mAnimatingImages = aAnimating;
}

already_AddRefed<Touch>
nsIDocument::CreateTouch(nsIDOMWindow* aView,
                         EventTarget* aTarget,
                         int32_t aIdentifier,
                         int32_t aPageX, int32_t aPageY,
                         int32_t aScreenX, int32_t aScreenY,
                         int32_t aClientX, int32_t aClientY,
                         int32_t aRadiusX, int32_t aRadiusY,
                         float aRotationAngle,
                         float aForce)
{
  nsRefPtr<Touch> touch = new Touch(aTarget,
                                    aIdentifier,
                                    aPageX, aPageY,
                                    aScreenX, aScreenY,
                                    aClientX, aClientY,
                                    aRadiusX, aRadiusY,
                                    aRotationAngle,
                                    aForce);
  return touch.forget();
}

already_AddRefed<nsDOMTouchList>
nsIDocument::CreateTouchList()
{
  nsRefPtr<nsDOMTouchList> retval = new nsDOMTouchList(ToSupports(this));
  return retval.forget();
}

already_AddRefed<nsDOMTouchList>
nsIDocument::CreateTouchList(Touch& aTouch,
                             const Sequence<OwningNonNull<Touch> >& aTouches)
{
  nsRefPtr<nsDOMTouchList> retval = new nsDOMTouchList(ToSupports(this));
  retval->Append(&aTouch);
  for (uint32_t i = 0; i < aTouches.Length(); ++i) {
    retval->Append(aTouches[i].get());
  }
  return retval.forget();
}

already_AddRefed<nsDOMTouchList>
nsIDocument::CreateTouchList(const Sequence<OwningNonNull<Touch> >& aTouches)
{
  nsRefPtr<nsDOMTouchList> retval = new nsDOMTouchList(ToSupports(this));
  for (uint32_t i = 0; i < aTouches.Length(); ++i) {
    retval->Append(aTouches[i].get());
  }
  return retval.forget();
}

already_AddRefed<nsDOMCaretPosition>
nsIDocument::CaretPositionFromPoint(float aX, float aY)
{
  nscoord x = nsPresContext::CSSPixelsToAppUnits(aX);
  nscoord y = nsPresContext::CSSPixelsToAppUnits(aY);
  nsPoint pt(x, y);

  FlushPendingNotifications(Flush_Layout);

  nsIPresShell *ps = GetShell();
  if (!ps) {
    return nullptr;
  }

  nsIFrame *rootFrame = ps->GetRootFrame();

  // XUL docs, unlike HTML, have no frame tree until everything's done loading
  if (!rootFrame) {
    return nullptr;
  }

  nsIFrame *ptFrame = nsLayoutUtils::GetFrameForPoint(rootFrame, pt, true,
                                                      false);
  if (!ptFrame) {
    return nullptr;
  }

  // GetContentOffsetsFromPoint requires frame-relative coordinates, so we need
  // to adjust to frame-relative coordinates before we can perform this call.
  // It should also not take into account the padding of the frame.
  nsPoint adjustedPoint = pt - ptFrame->GetOffsetTo(rootFrame);

  nsFrame::ContentOffsets offsets =
    ptFrame->GetContentOffsetsFromPoint(adjustedPoint);

  nsCOMPtr<nsIContent> node = offsets.content;
  uint32_t offset = offsets.offset;
  nsCOMPtr<nsIContent> anonNode = node;
  bool nodeIsAnonymous = node && node->IsInNativeAnonymousSubtree();
  if (nodeIsAnonymous) {
    node = ptFrame->GetContent();
    nsIContent* nonanon = node->FindFirstNonChromeOnlyAccessContent();
    nsCOMPtr<nsIDOMHTMLInputElement> input = do_QueryInterface(nonanon);
    nsCOMPtr<nsIDOMHTMLTextAreaElement> textArea = do_QueryInterface(nonanon);
    bool isText;
    if (textArea || (input &&
                     NS_SUCCEEDED(input->MozIsTextField(false, &isText)) &&
                     isText)) {
      // If the anonymous content node has a child, then we need to make sure
      // that we get the appropriate child, as otherwise the offset may not be
      // correct when we construct a range for it.
      nsCOMPtr<nsIContent> firstChild = anonNode->GetFirstChild();
      if (firstChild) {
        anonNode = firstChild;
      }

      if (textArea) {
        offset = nsContentUtils::GetAdjustedOffsetInTextControl(ptFrame, offset);
      }

      node = nonanon;
    } else {
      node = nullptr;
      offset = 0;
    }
  }

  nsRefPtr<nsDOMCaretPosition> aCaretPos = new nsDOMCaretPosition(node, offset);
  if (nodeIsAnonymous) {
    aCaretPos->SetAnonymousContentNode(anonNode);
  }
  return aCaretPos.forget();
}

NS_IMETHODIMP
nsDocument::CaretPositionFromPoint(float aX, float aY, nsISupports** aCaretPos)
{
  NS_ENSURE_ARG_POINTER(aCaretPos);
  *aCaretPos = nsIDocument::CaretPositionFromPoint(aX, aY).get();
  return NS_OK;
}

void
nsIDocument::ObsoleteSheet(nsIURI *aSheetURI, ErrorResult& rv)
{
  nsresult res = CSSLoader()->ObsoleteSheet(aSheetURI);
  if (NS_FAILED(res)) {
    rv.Throw(res);
  }
}

void
nsIDocument::ObsoleteSheet(const nsAString& aSheetURI, ErrorResult& rv)
{
  nsCOMPtr<nsIURI> uri;
  nsresult res = NS_NewURI(getter_AddRefs(uri), aSheetURI);
  if (NS_FAILED(res)) {
    rv.Throw(res);
    return;
  }
  res = CSSLoader()->ObsoleteSheet(uri);
  if (NS_FAILED(res)) {
    rv.Throw(res);
  }
}

nsIHTMLCollection*
nsIDocument::Children()
{
  if (!mChildrenCollection) {
    mChildrenCollection = new nsContentList(this, kNameSpaceID_Wildcard,
                                            nsGkAtoms::_asterix,
                                            nsGkAtoms::_asterix,
                                            false);
  }

  return mChildrenCollection;
}

uint32_t
nsIDocument::ChildElementCount()
{
  return Children()->Length();
}

namespace mozilla {

// Singleton class to manage the list of fullscreen documents which are the
// root of a branch which contains fullscreen documents. We maintain this list
// so that we can easily exit all windows from fullscreen when the user
// presses the escape key.
class FullscreenRoots {
public:
  // Adds a root to the manager. Adding a root multiple times does not result
  // in duplicate entries for that item, only one.
  static void Add(nsIDocument* aRoot);

  // Iterates over every root in the root list, and calls aFunction, passing
  // each root once to aFunction. It is safe to call Add() and Remove() while
  // iterating over the list (i.e. in aFunction). Documents that are removed
  // from the manager during traversal are not traversed, and documents that
  // are added to the manager during traversal are also not traversed.
  static void ForEach(void(*aFunction)(nsIDocument* aDoc));

  // Removes a specific root from the manager.
  static void Remove(nsIDocument* aRoot);

  // Returns true if all roots added to the list have been removed.
  static bool IsEmpty();

private:

  FullscreenRoots() {
    MOZ_COUNT_CTOR(FullscreenRoots);
  }
  ~FullscreenRoots() {
    MOZ_COUNT_DTOR(FullscreenRoots);
  }

  enum {
    NotFound = uint32_t(-1)
  };
  // Looks in mRoots for aRoot. Returns the index if found, otherwise NotFound.
  static uint32_t Find(nsIDocument* aRoot);

  // Returns true if aRoot is in the list of fullscreen roots.
  static bool Contains(nsIDocument* aRoot);

  // Singleton instance of the FullscreenRoots. This is instantiated when a
  // root is added, and it is deleted when the last root is removed.
  static FullscreenRoots* sInstance;

  // List of weak pointers to roots.
  nsTArray<nsWeakPtr> mRoots;
};

FullscreenRoots* FullscreenRoots::sInstance = nullptr;

/* static */
void
FullscreenRoots::ForEach(void(*aFunction)(nsIDocument* aDoc))
{
  if (!sInstance) {
    return;
  }
  // Create a copy of the roots array, and iterate over the copy. This is so
  // that if an element is removed from mRoots we don't mess up our iteration.
  nsTArray<nsWeakPtr> roots(sInstance->mRoots);
  // Call aFunction on all entries.
  for (uint32_t i = 0; i < roots.Length(); i++) {
    nsCOMPtr<nsIDocument> root = do_QueryReferent(roots[i]);
    // Check that the root isn't in the manager. This is so that new additions
    // while we were running don't get traversed.
    if (root && FullscreenRoots::Contains(root)) {
      aFunction(root);
    }
  }
}

/* static */
bool
FullscreenRoots::Contains(nsIDocument* aRoot)
{
  return FullscreenRoots::Find(aRoot) != NotFound;
}

/* static */
void
FullscreenRoots::Add(nsIDocument* aRoot)
{
  if (!FullscreenRoots::Contains(aRoot)) {
    if (!sInstance) {
      sInstance = new FullscreenRoots();
    }
    sInstance->mRoots.AppendElement(do_GetWeakReference(aRoot));
  }
}

/* static */
uint32_t
FullscreenRoots::Find(nsIDocument* aRoot)
{
  if (!sInstance) {
    return NotFound;
  }
  nsTArray<nsWeakPtr>& roots = sInstance->mRoots;
  for (uint32_t i = 0; i < roots.Length(); i++) {
    nsCOMPtr<nsIDocument> otherRoot(do_QueryReferent(roots[i]));
    if (otherRoot == aRoot) {
      return i;
    }
  }
  return NotFound;
}

/* static */
void
FullscreenRoots::Remove(nsIDocument* aRoot)
{
  uint32_t index = Find(aRoot);
  NS_ASSERTION(index != NotFound,
    "Should only try to remove roots which are still added!");
  if (index == NotFound || !sInstance) {
    return;
  }
  sInstance->mRoots.RemoveElementAt(index);
  if (sInstance->mRoots.IsEmpty()) {
    delete sInstance;
    sInstance = nullptr;
  }
}

/* static */
bool
FullscreenRoots::IsEmpty()
{
  return !sInstance;
}

} // end namespace mozilla.
using mozilla::FullscreenRoots;

nsIDocument*
nsDocument::GetFullscreenRoot()
{
  nsCOMPtr<nsIDocument> root = do_QueryReferent(mFullscreenRoot);
  return root;
}

void
nsDocument::SetFullscreenRoot(nsIDocument* aRoot)
{
  mFullscreenRoot = do_GetWeakReference(aRoot);
}

NS_IMETHODIMP
nsDocument::MozCancelFullScreen()
{
  nsIDocument::MozCancelFullScreen();
  return NS_OK;
}

void
nsIDocument::MozCancelFullScreen()
{
  // Only perform fullscreen changes if we're running in a webapp
  // same-origin to the web app, or if we're in a user generated event
  // handler.
  if (NodePrincipal()->GetAppStatus() >= nsIPrincipal::APP_STATUS_INSTALLED ||
      nsContentUtils::IsRequestFullScreenAllowed()) {
    RestorePreviousFullScreenState();
  }
}

// Runnable to set window full-screen mode. Used as a script runner
// to ensure we only call nsGlobalWindow::SetFullScreen() when it's safe to
// run script. nsGlobalWindow::SetFullScreen() dispatches a synchronous event
// (handled in chome code) which is unsafe to run if this is called in
// Element::UnbindFromTree().
class nsSetWindowFullScreen : public nsRunnable {
public:
  nsSetWindowFullScreen(nsIDocument* aDoc, bool aValue)
    : mDoc(aDoc), mValue(aValue) {}

  NS_IMETHOD Run()
  {
    if (mDoc->GetWindow()) {
      mDoc->GetWindow()->SetFullScreenInternal(mValue, false);
    }
    return NS_OK;
  }

private:
  nsCOMPtr<nsIDocument> mDoc;
  bool mValue;
};

static nsIDocument*
GetFullscreenRootDocument(nsIDocument* aDoc)
{
  if (!aDoc) {
    return nullptr;
  }
  nsIDocument* doc = aDoc;
  nsIDocument* parent;
  while ((parent = doc->GetParentDocument()) &&
         (!nsContentUtils::IsFullscreenApiContentOnly() ||
          !nsContentUtils::IsChromeDoc(parent))) {
    doc = parent;
  }
  return doc;
}

static void
SetWindowFullScreen(nsIDocument* aDoc, bool aValue)
{
  // Maintain list of fullscreen root documents.
  nsCOMPtr<nsIDocument> root = GetFullscreenRootDocument(aDoc);
  if (aValue) {
    FullscreenRoots::Add(root);
  } else {
    FullscreenRoots::Remove(root);
  }
  if (!nsContentUtils::IsFullscreenApiContentOnly()) {
    nsContentUtils::AddScriptRunner(new nsSetWindowFullScreen(aDoc, aValue));
  }
}

class nsCallExitFullscreen : public nsRunnable {
public:
  nsCallExitFullscreen(nsIDocument* aDoc)
    : mDoc(aDoc) {}
  NS_IMETHOD Run()
  {
    nsDocument::ExitFullscreen(mDoc);
    return NS_OK;
  }
private:
  nsCOMPtr<nsIDocument> mDoc;
};

/* static */
void
nsIDocument::ExitFullscreen(nsIDocument* aDoc, bool aRunAsync)
{
  if (aDoc && !aDoc->IsFullScreenDoc()) {
    return;
  }
  if (aRunAsync) {
    NS_DispatchToCurrentThread(new nsCallExitFullscreen(aDoc));
    return;
  }
  nsDocument::ExitFullscreen(aDoc);
}

// Returns true if the document is a direct child of a cross process parent
// mozbrowser iframe. This is the case when the document has a null parent,
// and its DocShell reports that it is a browser frame.
static bool
HasCrossProcessParent(nsIDocument* aDocument)
{
  if (XRE_GetProcessType() != GeckoProcessType_Content) {
    return false;
  }
  if (aDocument->GetParentDocument() != nullptr) {
    return false;
  }
  nsPIDOMWindow* win = aDocument->GetWindow();
  if (!win) {
    return false;
  }
  nsCOMPtr<nsIDocShell> docShell = win->GetDocShell();
  if (!docShell) {
    return false;
  }
  return docShell->GetIsBrowserOrApp();
}

static bool
CountFullscreenSubDocuments(nsIDocument* aDoc, void* aData)
{
  if (aDoc->IsFullScreenDoc()) {
    uint32_t* count = static_cast<uint32_t*>(aData);
    (*count)++;
  }
  return true;
}

static uint32_t
CountFullscreenSubDocuments(nsIDocument* aDoc)
{
  uint32_t count = 0;
  aDoc->EnumerateSubDocuments(CountFullscreenSubDocuments, &count);
  return count;
}

bool
nsDocument::IsFullscreenLeaf()
{
  // A fullscreen leaf document is fullscreen, and has no fullscreen
  // subdocuments.
  if (!IsFullScreenDoc()) {
    return false;
  }
  return CountFullscreenSubDocuments(this) == 0;
}

static bool
ResetFullScreen(nsIDocument* aDocument, void* aData)
{
  if (aDocument->IsFullScreenDoc()) {
    NS_ASSERTION(CountFullscreenSubDocuments(aDocument) <= 1,
        "Should have at most 1 fullscreen subdocument.");
    static_cast<nsDocument*>(aDocument)->CleanupFullscreenState();
    NS_ASSERTION(!aDocument->IsFullScreenDoc(), "Should reset full-screen");
    nsTArray<nsIDocument*>* changed = reinterpret_cast<nsTArray<nsIDocument*>*>(aData);
    changed->AppendElement(aDocument);

    if (HasCrossProcessParent(aDocument)) {
      // We're at the top of the content-process side doc tree. Ask the parent
      // process to exit fullscreen.
      nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
      os->NotifyObservers(aDocument, "ask-parent-to-exit-fullscreen", nullptr);
    }

    // Dispatch a notification so that if this document has any
    // cross-process subdocuments, they'll be notified to exit fullscreen.
    // The BrowserElementParent listens for this event and performs the
    // cross process notification if it has a remote child process.
    nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
    os->NotifyObservers(aDocument, "ask-children-to-exit-fullscreen", nullptr);

    aDocument->EnumerateSubDocuments(ResetFullScreen, aData);
  }
  return true;
}

static void
ExitFullscreenInDocTree(nsIDocument* aMaybeNotARootDoc)
{
  MOZ_ASSERT(aMaybeNotARootDoc);
  nsCOMPtr<nsIDocument> root = aMaybeNotARootDoc->GetFullscreenRoot();
  NS_ASSERTION(root, "Should have root when in fullscreen!");
  if (!root) {
    return;
  }
  NS_ASSERTION(root->IsFullScreenDoc(),
    "Fullscreen root should be a fullscreen doc...");

  // Stores a list of documents to which we must dispatch "mozfullscreenchange".
  // We're required by the spec to dispatch the events in leaf-to-root
  // order when exiting fullscreen, but we traverse the doctree in a
  // root-to-leaf order, so we save references to the documents we must
  // dispatch to so that we dispatch in the specified order.
  nsAutoTArray<nsIDocument*, 8> changed;

  // Walk the tree of fullscreen documents, and reset their fullscreen state.
  ResetFullScreen(root, static_cast<void*>(&changed));

  // Dispatch "mozfullscreenchange" events. Note this loop is in reverse
  // order so that the events for the leaf document arrives before the root
  // document, as required by the spec.
  for (uint32_t i = 0; i < changed.Length(); ++i) {
    DispatchFullScreenChange(changed[changed.Length() - i - 1]);
  }

  NS_ASSERTION(!root->IsFullScreenDoc(),
    "Fullscreen root should no longer be a fullscreen doc...");

  // Move the top-level window out of fullscreen mode.
  SetWindowFullScreen(root, false);
}

/* static */
void
nsDocument::ExitFullscreen(nsIDocument* aDoc)
{
  // Unlock the pointer, if it's locked.
  nsCOMPtr<Element> pointerLockedElement =
    do_QueryReferent(nsEventStateManager::sPointerLockedElement);
  if (pointerLockedElement) {
    UnlockPointer();
  }

  if (aDoc)  {
    ExitFullscreenInDocTree(aDoc);
    return;
  }

  // Clear fullscreen stacks in all fullscreen roots' descendant documents.
  FullscreenRoots::ForEach(&ExitFullscreenInDocTree);
  NS_ASSERTION(FullscreenRoots::IsEmpty(),
      "Should have exited all fullscreen roots from fullscreen");
}

bool
GetFullscreenLeaf(nsIDocument* aDoc, void* aData)
{
  if (aDoc->IsFullscreenLeaf()) {
    nsIDocument** result = static_cast<nsIDocument**>(aData);
    *result = aDoc;
    return false;
  } else if (aDoc->IsFullScreenDoc()) {
    aDoc->EnumerateSubDocuments(GetFullscreenLeaf, aData);
  }
  return true;
}

static nsIDocument*
GetFullscreenLeaf(nsIDocument* aDoc)
{
  nsIDocument* leaf = nullptr;
  GetFullscreenLeaf(aDoc, &leaf);
  if (leaf) {
    return leaf;
  }
  // Otherwise we could be either in a non-fullscreen doc tree, or we're
  // below the fullscreen doc. Start the search from the root.
  nsIDocument* root = GetFullscreenRootDocument(aDoc);
  // Check that the root is actually fullscreen so we don't waste time walking
  // around its descendants.
  if (!root->IsFullScreenDoc()) {
    return nullptr;
  }
  GetFullscreenLeaf(root, &leaf);
  return leaf;
}

void
nsDocument::RestorePreviousFullScreenState()
{
  NS_ASSERTION(!IsFullScreenDoc() || !FullscreenRoots::IsEmpty(),
    "Should have at least 1 fullscreen root when fullscreen!");
  NS_ASSERTION(!nsContentUtils::IsFullscreenApiContentOnly() ||
               !nsContentUtils::IsChromeDoc(this),
               "Should not run RestorePreviousFullScreenState() on "
               "chrome document when fullscreen is content only");

  if (!IsFullScreenDoc() || !GetWindow() || FullscreenRoots::IsEmpty()) {
    return;
  }

  // If fullscreen mode is updated the pointer should be unlocked
  nsCOMPtr<Element> pointerLockedElement =
    do_QueryReferent(nsEventStateManager::sPointerLockedElement);
  if (pointerLockedElement) {
    UnlockPointer();
  }

  nsCOMPtr<nsIDocument> fullScreenDoc = GetFullscreenLeaf(this);

  // The fullscreen document may contain a <iframe mozbrowser> element which
  // has a cross process child. So send a notification so that its browser
  // parent will send a message to its child process to also exit fullscreen.
  nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
  os->NotifyObservers(fullScreenDoc, "ask-children-to-exit-fullscreen", nullptr);

  // Clear full-screen stacks in all descendant in process documents, bottom up.
  nsIDocument* doc = fullScreenDoc;
  while (doc != this) {
    NS_ASSERTION(doc->IsFullScreenDoc(), "Should be full-screen doc");
    static_cast<nsDocument*>(doc)->CleanupFullscreenState();
    UnlockPointer();
    DispatchFullScreenChange(doc);
    doc = doc->GetParentDocument();
  }

  // Roll-back full-screen state to previous full-screen element.
  NS_ASSERTION(doc == this, "Must have reached this doc.");
  while (doc != nullptr) {
    static_cast<nsDocument*>(doc)->FullScreenStackPop();
    UnlockPointer();
    DispatchFullScreenChange(doc);
    if (static_cast<nsDocument*>(doc)->mFullScreenStack.IsEmpty()) {
      if (HasCrossProcessParent(doc)) {
        // Send notification to the parent process to tell it to rollback to
        // the previous fullscreen elements in its fullscreen element stacks.
        nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
        os->NotifyObservers(doc, "ask-parent-to-rollback-fullscreen", nullptr);
      }
      // Full-screen stack in document is empty. Go back up to the parent
      // document. We'll pop the containing element off its stack, and use
      // its next full-screen element as the full-screen element.
      static_cast<nsDocument*>(doc)->CleanupFullscreenState();
      doc = doc->GetParentDocument();
    } else {
      // Else we popped the top of the stack, and there's still another
      // element in there, so that will become the full-screen element.
      if (fullScreenDoc != doc) {
        // We've popped so enough off the stack that we've rolled back to
        // a fullscreen element in a parent document. If this document isn't
        // approved for fullscreen, or if it's cross origin, dispatch an
        // event to chrome so it knows to show the authorization/warning UI.
        if (!nsContentUtils::HaveEqualPrincipals(fullScreenDoc, doc) ||
            (!nsContentUtils::IsSitePermAllow(doc->NodePrincipal(), "fullscreen") &&
             !static_cast<nsDocument*>(doc)->mIsApprovedForFullscreen)) {
          nsRefPtr<nsAsyncDOMEvent> e =
            new nsAsyncDOMEvent(doc,
                                NS_LITERAL_STRING("MozEnteredDomFullscreen"),
                                true,
                                true);
          e->PostDOMEvent();
        }
      }

      if (!nsContentUtils::HaveEqualPrincipals(doc, fullScreenDoc)) {
        // The origin which is fullscreen changed. Send a notification to
        // the root process so that a warning or approval UI can be shown
        // as necessary.
        nsAutoString origin;
        nsContentUtils::GetUTFOrigin(doc->NodePrincipal(), origin);
        nsIDocument* root = GetFullscreenRootDocument(doc);
        nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
        os->NotifyObservers(root, "fullscreen-origin-change", origin.get());
      }

      break;
    }
  }

  if (doc == nullptr) {
    // We moved all documents in this doctree out of fullscreen mode,
    // move the top-level window out of fullscreen mode.
    NS_ASSERTION(!GetFullscreenRootDocument(this)->IsFullScreenDoc(),
      "Should have cleared all docs' stacks");
    SetWindowFullScreen(this, false);
  }
}

bool
nsDocument::IsFullScreenDoc()
{
  return GetFullScreenElement() != nullptr;
}

class nsCallRequestFullScreen : public nsRunnable
{
public:
  nsCallRequestFullScreen(Element* aElement)
    : mElement(aElement),
      mDoc(aElement->OwnerDoc()),
      mWasCallerChrome(nsContentUtils::IsCallerChrome()),
      mHadRequestPending(static_cast<nsDocument*>(mDoc.get())->
                           mAsyncFullscreenPending)
  {
    static_cast<nsDocument*>(mDoc.get())->
      mAsyncFullscreenPending = true;
  }

  NS_IMETHOD Run()
  {
    static_cast<nsDocument*>(mDoc.get())->
      mAsyncFullscreenPending = mHadRequestPending;
    nsDocument* doc = static_cast<nsDocument*>(mDoc.get());
    doc->RequestFullScreen(mElement,
                           mWasCallerChrome,
                           /* aNotifyOnOriginChange */ true);
    return NS_OK;
  }

  nsRefPtr<Element> mElement;
  nsCOMPtr<nsIDocument> mDoc;
  bool mWasCallerChrome;
  bool mHadRequestPending;
};

void
nsDocument::AsyncRequestFullScreen(Element* aElement)
{
  NS_ASSERTION(aElement,
    "Must pass non-null element to nsDocument::AsyncRequestFullScreen");
  if (!aElement) {
    return;
  }
  // Request full-screen asynchronously.
  nsCOMPtr<nsIRunnable> event(new nsCallRequestFullScreen(aElement));
  NS_DispatchToCurrentThread(event);
}

static void
LogFullScreenDenied(bool aLogFailure, const char* aMessage, nsIDocument* aDoc)
{
  if (!aLogFailure) {
    return;
  }
  nsRefPtr<nsAsyncDOMEvent> e =
    new nsAsyncDOMEvent(aDoc,
                        NS_LITERAL_STRING("mozfullscreenerror"),
                        true,
                        false);
  e->PostDOMEvent();
  nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,
                                  "DOM", aDoc,
                                  nsContentUtils::eDOM_PROPERTIES,
                                  aMessage);
}

nsresult
nsDocument::AddFullscreenApprovedObserver()
{
  if (mHasFullscreenApprovedObserver ||
      !Preferences::GetBool("full-screen-api.approval-required")) {
    return NS_OK;
  }

  nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
  NS_ENSURE_TRUE(os, NS_ERROR_FAILURE);

  nsresult res = os->AddObserver(this, "fullscreen-approved", true);
  NS_ENSURE_SUCCESS(res, res);

  mHasFullscreenApprovedObserver = true;

  return NS_OK;
}

nsresult
nsDocument::RemoveFullscreenApprovedObserver()
{
  if (!mHasFullscreenApprovedObserver) {
    return NS_OK;
  }
  nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
  NS_ENSURE_TRUE(os, NS_ERROR_FAILURE);

  nsresult res = os->RemoveObserver(this, "fullscreen-approved");
  NS_ENSURE_SUCCESS(res, res);

  mHasFullscreenApprovedObserver = false;

  return NS_OK;
}

void
nsDocument::CleanupFullscreenState()
{
  if (!mFullScreenStack.IsEmpty()) {
    // The top element in the full-screen stack will have full-screen
    // style bits set on it and its ancestors. Remove the style bits.
    // Note the non-top elements won't have the style bits set.
    Element* top = FullScreenStackTop();
    NS_ASSERTION(top, "Should have a top when full-screen stack isn't empty");
    if (top) {
      nsEventStateManager::SetFullScreenState(top, false);
    }
    mFullScreenStack.Clear();
  }
  SetApprovedForFullscreen(false);
  RemoveFullscreenApprovedObserver();
  mFullscreenRoot = nullptr;
}

bool
nsDocument::FullScreenStackPush(Element* aElement)
{
  NS_ASSERTION(aElement, "Must pass non-null to FullScreenStackPush()");
  Element* top = FullScreenStackTop();
  if (top == aElement || !aElement) {
    return false;
  }
  if (top) {
    // We're pushing a new element onto the full-screen stack, so we must
    // remove the ancestor and full-screen styles from the former top of the
    // stack.
    nsEventStateManager::SetFullScreenState(top, false);
  }
  nsEventStateManager::SetFullScreenState(aElement, true);
  mFullScreenStack.AppendElement(do_GetWeakReference(aElement));
  NS_ASSERTION(GetFullScreenElement() == aElement, "Should match");
  return true;
}

void
nsDocument::FullScreenStackPop()
{
  if (mFullScreenStack.IsEmpty()) {
    return;
  }

  // Remove styles from existing top element.
  Element* top = FullScreenStackTop();
  nsEventStateManager::SetFullScreenState(top, false);

  // Remove top element. Note the remaining top element in the stack
  // will not have full-screen style bits set, so we will need to restore
  // them on the new top element before returning.
  uint32_t last = mFullScreenStack.Length() - 1;
  mFullScreenStack.RemoveElementAt(last);

  // Pop from the stack null elements (references to elements which have
  // been GC'd since they were added to the stack) and elements which are
  // no longer in this document.
  while (!mFullScreenStack.IsEmpty()) {
    Element* element = FullScreenStackTop();
    if (!element || !element->IsInDoc() || element->OwnerDoc() != this) {
      NS_ASSERTION(!element->IsFullScreenAncestor(),
                   "Should have already removed full-screen styles");
      uint32_t last = mFullScreenStack.Length() - 1;
      mFullScreenStack.RemoveElementAt(last);
    } else {
      // The top element of the stack is now an in-doc element. Apply the
      // full-screen styles and return.
      nsEventStateManager::SetFullScreenState(element, true);
      break;
    }
  }
}

Element*
nsDocument::FullScreenStackTop()
{
  if (mFullScreenStack.IsEmpty()) {
    return nullptr;
  }
  uint32_t last = mFullScreenStack.Length() - 1;
  nsCOMPtr<Element> element(do_QueryReferent(mFullScreenStack[last]));
  NS_ASSERTION(element, "Should have full-screen element!");
  NS_ASSERTION(element->IsInDoc(), "Full-screen element should be in doc");
  NS_ASSERTION(element->OwnerDoc() == this, "Full-screen element should be in this doc");
  return element;
}

// Returns true if aDoc is in the focused tab in the active window.
static bool
IsInActiveTab(nsIDocument* aDoc)
{
  nsCOMPtr<nsISupports> container = aDoc->GetContainer();
  nsCOMPtr<nsIDocShell> docshell = do_QueryInterface(container);
  if (!docshell) {
    return false;
  }

  bool isActive = false;
  docshell->GetIsActive(&isActive);
  if (!isActive) {
    return false;
  }

  nsCOMPtr<nsIDocShellTreeItem> dsti = do_QueryInterface(container);
  if (!dsti) {
    return false;
  }
  nsCOMPtr<nsIDocShellTreeItem> rootItem;
  dsti->GetRootTreeItem(getter_AddRefs(rootItem));
  if (!rootItem) {
    return false;
  }
  nsCOMPtr<nsIDOMWindow> rootWin = do_GetInterface(rootItem);
  if (!rootWin) {
    return false;
  }

  nsIFocusManager* fm = nsFocusManager::GetFocusManager();
  if (!fm) {
    return false;
  }

  nsCOMPtr<nsIDOMWindow> activeWindow;
  fm->GetActiveWindow(getter_AddRefs(activeWindow));
  if (!activeWindow) {
    return false;
  }

  return activeWindow == rootWin;
}

nsresult nsDocument::RemoteFrameFullscreenChanged(nsIDOMElement* aFrameElement,
                                                  const nsAString& aOrigin)
{
  // Ensure the frame element is the fullscreen element in this document.
  // If the frame element is already the fullscreen element in this document,
  // this has no effect.
  nsCOMPtr<nsIContent> content(do_QueryInterface(aFrameElement));
  RequestFullScreen(content->AsElement(),
                    /* aWasCallerChrome */ false,
                    /* aNotifyOnOriginChange */ false);

  // Origin changed in child process, send notifiction, so that chrome can
  // update the UI to reflect the fullscreen origin change if necessary.
  // The BrowserElementChild listens on this, and forwards it over its
  // parent process, where it is redispatched. Chrome (in the root process,
  // which could be *this* process) listens for this notification so that
  // it can show a warning or approval UI.
  if (!aOrigin.IsEmpty()) {
    nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
    os->NotifyObservers(GetFullscreenRootDocument(this),
                        "fullscreen-origin-change",
                        PromiseFlatString(aOrigin).get());
  }

  return NS_OK;
}

nsresult nsDocument::RemoteFrameFullscreenReverted()
{
  RestorePreviousFullScreenState();
  return NS_OK;
}

void
nsDocument::RequestFullScreen(Element* aElement,
                              bool aWasCallerChrome,
                              bool aNotifyOnOriginChange)
{
  NS_ASSERTION(aElement,
    "Must pass non-null element to nsDocument::RequestFullScreen");
  if (!aElement || aElement == GetFullScreenElement()) {
    return;
  }
  if (!aElement->IsInDoc()) {
    LogFullScreenDenied(true, "FullScreenDeniedNotInDocument", this);
    return;
  }
  if (aElement->OwnerDoc() != this) {
    LogFullScreenDenied(true, "FullScreenDeniedMovedDocument", this);
    return;
  }
  if (!GetWindow()) {
    LogFullScreenDenied(true, "FullScreenDeniedLostWindow", this);
    return;
  }
  if (nsContentUtils::IsFullscreenApiContentOnly() &&
      nsContentUtils::IsChromeDoc(this)) {
    // Block fullscreen requests in the chrome document when the fullscreen API
    // is configured for content only.
    LogFullScreenDenied(true, "FullScreenDeniedContentOnly", this);
    return;
  }
  if (!IsFullScreenEnabled(aWasCallerChrome, true)) {
    // IsFullScreenEnabled calls LogFullScreenDenied, no need to log.
    return;
  }
  if (GetFullScreenElement() &&
      !nsContentUtils::ContentIsDescendantOf(aElement, GetFullScreenElement())) {
    // If this document is full-screen, only grant full-screen requests from
    // a descendant of the current full-screen element.
    LogFullScreenDenied(true, "FullScreenDeniedNotDescendant", this);
    return;
  }
  if (!nsContentUtils::IsChromeDoc(this) && !IsInActiveTab(this)) {
    LogFullScreenDenied(true, "FullScreenDeniedNotFocusedTab", this);
    return;
  }
  // Deny requests when a windowed plugin is focused.
  nsIFocusManager* fm = nsFocusManager::GetFocusManager();
  if (!fm) {
    NS_WARNING("Failed to retrieve focus manager in full-screen request.");
    return;
  }
  nsCOMPtr<nsIDOMElement> focusedElement;
  fm->GetFocusedElement(getter_AddRefs(focusedElement));
  if (focusedElement) {
    nsCOMPtr<nsIContent> content = do_QueryInterface(focusedElement);
    if (nsContentUtils::HasPluginWithUncontrolledEventDispatch(content)) {
      LogFullScreenDenied(true, "FullScreenDeniedFocusedPlugin", this);
      return;
    }
  }

  // Stash a reference to any existing fullscreen doc, we'll use this later
  // to detect if the origin which is fullscreen has changed.
  nsCOMPtr<nsIDocument> previousFullscreenDoc = GetFullscreenLeaf(this);

  AddFullscreenApprovedObserver();

  // Stores a list of documents which we must dispatch "mozfullscreenchange"
  // too. We're required by the spec to dispatch the events in root-to-leaf
  // order, but we traverse the doctree in a leaf-to-root order, so we save
  // references to the documents we must dispatch to so that we get the order
  // as specified.
  nsAutoTArray<nsIDocument*, 8> changed;

  // Remember the root document, so that if a full-screen document is hidden
  // we can reset full-screen state in the remaining visible full-screen documents.
  nsIDocument* fullScreenRootDoc = GetFullscreenRootDocument(this);
  if (fullScreenRootDoc->IsFullScreenDoc()) {
    // A document is already in fullscreen, unlock the mouse pointer
    // before setting a new document to fullscreen
    UnlockPointer();
  }

  // If a document is already in fullscreen, then unlock the mouse pointer
  // before setting a new document to fullscreen
  nsCOMPtr<Element> pointerLockedElement =
    do_QueryReferent(nsEventStateManager::sPointerLockedElement);
  if (pointerLockedElement) {
    UnlockPointer();
  }

  // Set the full-screen element. This sets the full-screen style on the
  // element, and the full-screen-ancestor styles on ancestors of the element
  // in this document.
  DebugOnly<bool> x = FullScreenStackPush(aElement);
  NS_ASSERTION(x, "Full-screen state of requesting doc should always change!");
  changed.AppendElement(this);

  // Propagate up the document hierarchy, setting the full-screen element as
  // the element's container in ancestor documents. This also sets the
  // appropriate css styles as well. Note we don't propagate down the
  // document hierarchy, the full-screen element (or its container) is not
  // visible there. Stop when we reach the root document.
  nsIDocument* child = this;
  while (true) {
    child->SetFullscreenRoot(fullScreenRootDoc);
    NS_ASSERTION(child->GetFullscreenRoot() == fullScreenRootDoc,
        "Fullscreen root should be set!");
    if (child == fullScreenRootDoc) {
      break;
    }
    nsIDocument* parent = child->GetParentDocument();
    Element* element = parent->FindContentForSubDocument(child)->AsElement();
    if (static_cast<nsDocument*>(parent)->FullScreenStackPush(element)) {
      changed.AppendElement(parent);
      child = parent;
    } else {
      // We've reached either the root, or a point in the doctree where the
      // new full-screen element container is the same as the previous
      // full-screen element's container. No more changes need to be made
      // to the full-screen stacks of documents further up the tree.
      break;
    }
  }

  // Dispatch "mozfullscreenchange" events. Note this loop is in reverse
  // order so that the events for the root document arrives before the leaf
  // document, as required by the spec.
  for (uint32_t i = 0; i < changed.Length(); ++i) {
    DispatchFullScreenChange(changed[changed.Length() - i - 1]);
  }

  // If this document hasn't already been approved in this session,
  // check to see if the user has granted the fullscreen access
  // to the document's principal's host, if it has one. Note that documents
  // in web apps which are the same origin as the web app are considered
  // trusted and so are automatically approved.
  if (!mIsApprovedForFullscreen) {
    mIsApprovedForFullscreen =
      !Preferences::GetBool("full-screen-api.approval-required") ||
      NodePrincipal()->GetAppStatus() >= nsIPrincipal::APP_STATUS_INSTALLED ||
      nsContentUtils::IsSitePermAllow(NodePrincipal(), "fullscreen");
  }

  // If this document, or a document with the same principal has not
  // already been approved for fullscreen this fullscreen-session, dispatch
  // an event so that chrome knows to pop up a warning/approval UI.
  // Note previousFullscreenDoc=nullptr upon first entry, so we always
  // take this path on the first time we enter fullscreen in a fullscreen
  // session.
  if (!mIsApprovedForFullscreen ||
      !nsContentUtils::HaveEqualPrincipals(previousFullscreenDoc, this)) {
    nsRefPtr<nsAsyncDOMEvent> e =
      new nsAsyncDOMEvent(this,
                          NS_LITERAL_STRING("MozEnteredDomFullscreen"),
                          true,
                          true);
    e->PostDOMEvent();
  }

#ifdef DEBUG
  // Note assertions must run before SetWindowFullScreen() as that does
  // synchronous event dispatch which can run script which exits full-screen!
  NS_ASSERTION(GetFullScreenElement() == aElement,
               "Full-screen element should be the requested element!");
  NS_ASSERTION(IsFullScreenDoc(), "Should be full-screen doc");
  nsCOMPtr<nsIDOMElement> fse;
  GetMozFullScreenElement(getter_AddRefs(fse));
  nsCOMPtr<nsIContent> c(do_QueryInterface(fse));
  NS_ASSERTION(c->AsElement() == aElement,
    "GetMozFullScreenElement should match GetFullScreenElement()");
#endif

  // The origin which is fullscreen changed, send a notifiction so that the
  // root document knows the origin of the document which requested fullscreen.
  // This is used for the fullscreen approval UI. If we're in a child
  // process, the root BrowserElementChild listens for this notification,
  // and forwards it across to its BrowserElementParent, which
  // re-broadcasts the message for the root document in its process.
  if (aNotifyOnOriginChange &&
      !nsContentUtils::HaveEqualPrincipals(previousFullscreenDoc, this)) {
    nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
    nsIDocument* root = GetFullscreenRootDocument(this);
    nsAutoString origin;
    nsContentUtils::GetUTFOrigin(NodePrincipal(), origin);
    os->NotifyObservers(root, "fullscreen-origin-change", origin.get());
  }

  // Make the window full-screen. Note we must make the state changes above
  // before making the window full-screen, as then the document reports as
  // being in full-screen mode when the chrome "fullscreen" event fires,
  // enabling chrome to distinguish between browser and dom full-screen
  // modes. Also note that nsGlobalWindow::SetFullScreen() (which
  // SetWindowFullScreen() calls) proxies to the root window in its hierarchy,
  // and does not operate on the a per-nsIDOMWindow basis.
  SetWindowFullScreen(this, true);
}

NS_IMETHODIMP
nsDocument::GetMozFullScreenElement(nsIDOMElement **aFullScreenElement)
{
  ErrorResult rv;
  Element* el = GetMozFullScreenElement(rv);
  if (rv.Failed()) {
    return rv.ErrorCode();
  }
  nsCOMPtr<nsIDOMElement> retval = do_QueryInterface(el);
  retval.forget(aFullScreenElement);
  return NS_OK;
}

Element*
nsDocument::GetMozFullScreenElement(ErrorResult& rv)
{
  if (IsFullScreenDoc()) {
    // Must have a full-screen element while in full-screen mode.
    Element* el = GetFullScreenElement();
    if (!el) {
      rv.Throw(NS_ERROR_UNEXPECTED);
    }
    return el;
  }
  return nullptr;
}

Element*
nsDocument::GetFullScreenElement()
{
  Element* element = FullScreenStackTop();
  NS_ASSERTION(!element ||
               element->IsFullScreenAncestor(),
    "Fullscreen element should have fullscreen styles applied");
  return element;
}

NS_IMETHODIMP
nsDocument::GetMozFullScreen(bool *aFullScreen)
{
  *aFullScreen = MozFullScreen();
  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetMozFullScreenEnabled(bool *aFullScreen)
{
  NS_ENSURE_ARG_POINTER(aFullScreen);
  *aFullScreen = MozFullScreenEnabled();
  return NS_OK;
}

bool
nsDocument::MozFullScreenEnabled()
{
  return IsFullScreenEnabled(nsContentUtils::IsCallerChrome(), false);
}

static bool
HasFullScreenSubDocument(nsIDocument* aDoc)
{
  uint32_t count = CountFullscreenSubDocuments(aDoc);
  NS_ASSERTION(count <= 1, "Fullscreen docs should have at most 1 fullscreen child!");
  return count >= 1;
}

bool
nsDocument::IsFullScreenEnabled(bool aCallerIsChrome, bool aLogFailure)
{
  if (nsContentUtils::IsFullScreenApiEnabled() && aCallerIsChrome) {
    // Chrome code can always use the full-screen API, provided it's not
    // explicitly disabled. Note IsCallerChrome() returns true when running
    // in an nsRunnable, so don't use GetMozFullScreenEnabled() from an
    // nsRunnable!
    return true;
  }

  if (!nsContentUtils::IsFullScreenApiEnabled()) {
    LogFullScreenDenied(aLogFailure, "FullScreenDeniedDisabled", this);
    return false;
  }
  if (!IsVisible()) {
    LogFullScreenDenied(aLogFailure, "FullScreenDeniedHidden", this);
    return false;
  }
  if (HasFullScreenSubDocument(this)) {
    LogFullScreenDenied(aLogFailure, "FullScreenDeniedSubDocFullScreen", this);
    return false;
  }

  // Ensure that all ancestor <iframe> elements have the allowfullscreen
  // boolean attribute set.
  nsCOMPtr<nsIDocShell> docShell = do_QueryReferent(mDocumentContainer);
  bool allowed = false;
  if (docShell) {
    docShell->GetFullscreenAllowed(&allowed);
  }
  if (!allowed) {
    LogFullScreenDenied(aLogFailure, "FullScreenDeniedIframeNotAllowed", this);
  }

  return allowed;
}

static void
DispatchPointerLockChange(nsIDocument* aTarget)
{
  if (!aTarget) {
    return;
  }

  nsRefPtr<nsAsyncDOMEvent> e =
    new nsAsyncDOMEvent(aTarget,
                        NS_LITERAL_STRING("mozpointerlockchange"),
                        true,
                        false);
  e->PostDOMEvent();
}

static void
DispatchPointerLockError(nsIDocument* aTarget)
{
  if (!aTarget) {
    return;
  }

  nsRefPtr<nsAsyncDOMEvent> e =
    new nsAsyncDOMEvent(aTarget,
                        NS_LITERAL_STRING("mozpointerlockerror"),
                        true,
                        false);
  e->PostDOMEvent();
}

mozilla::StaticRefPtr<nsPointerLockPermissionRequest> gPendingPointerLockRequest;

class nsPointerLockPermissionRequest : public nsRunnable,
                                       public nsIContentPermissionRequest
{
public:
  nsPointerLockPermissionRequest(Element* aElement, bool aUserInputOrChromeCaller)
  : mElement(do_GetWeakReference(aElement)),
    mDocument(do_GetWeakReference(aElement->OwnerDoc())),
    mUserInputOrChromeCaller(aUserInputOrChromeCaller) {}

  virtual ~nsPointerLockPermissionRequest() {}

  NS_DECL_ISUPPORTS
  NS_DECL_NSICONTENTPERMISSIONREQUEST

  NS_IMETHOD Run()
  {
    nsCOMPtr<Element> e = do_QueryReferent(mElement);
    nsCOMPtr<nsIDocument> d = do_QueryReferent(mDocument);
    if (!e || !d || gPendingPointerLockRequest != this ||
        e->GetCurrentDoc() != d) {
      Handled();
      DispatchPointerLockError(d);
      return NS_OK;
    }

    // We're about to enter fullscreen mode.
    nsDocument* doc = static_cast<nsDocument*>(d.get());
    if (doc->mAsyncFullscreenPending ||
        (doc->mHasFullscreenApprovedObserver && !doc->mIsApprovedForFullscreen)) {
      // We're still waiting for approval.
      return NS_OK;
    }

    if (doc->mIsApprovedForFullscreen || doc->mAllowRelocking) {
      Allow();
      return NS_OK;
    }

    // In non-fullscreen mode user input (or chrome caller) is required!
    // Also, don't let the page to try to get the permission too many times.
    if (!mUserInputOrChromeCaller ||
        doc->mCancelledPointerLockRequests > 2) {
      Handled();
      DispatchPointerLockError(d);
      return NS_OK;
    }

    // Handling a request from user input in non-fullscreen mode.
    // Do a normal permission check.
    nsCOMPtr<nsIContentPermissionPrompt> prompt =
      do_CreateInstance(NS_CONTENT_PERMISSION_PROMPT_CONTRACTID);
    if (prompt) {
      prompt->Prompt(this);
    }

    return NS_OK;
  }

  void Handled()
  {
    mElement = nullptr;
    mDocument = nullptr;
    if (gPendingPointerLockRequest == this) {
      gPendingPointerLockRequest = nullptr;
    }
  }

  nsWeakPtr mElement;
  nsWeakPtr mDocument;
  bool mUserInputOrChromeCaller;
};

NS_IMPL_ISUPPORTS_INHERITED1(nsPointerLockPermissionRequest,
                             nsRunnable,
                             nsIContentPermissionRequest)

NS_IMETHODIMP
nsPointerLockPermissionRequest::GetType(nsACString& aType)
{
  aType = "pointerLock";
  return NS_OK;
}

NS_IMETHODIMP
nsPointerLockPermissionRequest::GetAccess(nsACString& aAccess)
{
  aAccess = "unused";
  return NS_OK;
}

NS_IMETHODIMP
nsPointerLockPermissionRequest::GetPrincipal(nsIPrincipal** aPrincipal)
{
  nsCOMPtr<nsIDocument> d = do_QueryReferent(mDocument);
  if (d) {
    NS_ADDREF(*aPrincipal = d->NodePrincipal());
  }
  return NS_OK;
}

NS_IMETHODIMP
nsPointerLockPermissionRequest::GetWindow(nsIDOMWindow** aWindow)
{
  nsCOMPtr<nsIDocument> d = do_QueryReferent(mDocument);
  if (d) {
    NS_IF_ADDREF(*aWindow = d->GetInnerWindow());
  }
  return NS_OK;
}

NS_IMETHODIMP
nsPointerLockPermissionRequest::GetElement(nsIDOMElement** aElement)
{
  // It is enough to implement GetWindow.
  *aElement = nullptr;
  return NS_OK;
}

NS_IMETHODIMP
nsPointerLockPermissionRequest::Cancel()
{
  nsCOMPtr<nsIDocument> d = do_QueryReferent(mDocument);
  Handled();
  if (d) {
    static_cast<nsDocument*>(d.get())->mCancelledPointerLockRequests++;
    DispatchPointerLockError(d);
  }
  return NS_OK;
}

NS_IMETHODIMP
nsPointerLockPermissionRequest::Allow()
{
  nsCOMPtr<Element> e = do_QueryReferent(mElement);
  nsCOMPtr<nsIDocument> doc = do_QueryReferent(mDocument);
  nsDocument* d = static_cast<nsDocument*>(doc.get());
  if (!e || !d || gPendingPointerLockRequest != this ||
      e->GetCurrentDoc() != d ||
      (!mUserInputOrChromeCaller && !d->mIsApprovedForFullscreen)) {
    Handled();
    DispatchPointerLockError(d);
    return NS_OK;
  }

  // Mark handled here so that we don't need to call it everywhere below.
  Handled();

  nsCOMPtr<Element> pointerLockedElement =
    do_QueryReferent(nsEventStateManager::sPointerLockedElement);
  if (e == pointerLockedElement) {
    DispatchPointerLockChange(d);
    return NS_OK;
  }

  // Note, we must bypass focus change, so pass true as the last parameter!
  if (!d->ShouldLockPointer(e, pointerLockedElement, true)) {
    DispatchPointerLockError(d);
    return NS_OK;
  }

  if (!d->SetPointerLock(e, NS_STYLE_CURSOR_NONE)) {
    DispatchPointerLockError(d);
    return NS_OK;
  }

  d->mCancelledPointerLockRequests = 0;
  e->SetPointerLock();
  nsEventStateManager::sPointerLockedElement = do_GetWeakReference(e);
  nsEventStateManager::sPointerLockedDoc = do_GetWeakReference(doc);
  NS_ASSERTION(nsEventStateManager::sPointerLockedElement &&
               nsEventStateManager::sPointerLockedDoc,
               "aElement and this should support weak references!");

  DispatchPointerLockChange(d);
  return NS_OK;
}

void
nsDocument::SetApprovedForFullscreen(bool aIsApproved)
{
  mIsApprovedForFullscreen = aIsApproved;
}

nsresult
nsDocument::Observe(nsISupports *aSubject,
                    const char *aTopic,
                    const PRUnichar *aData)
{
  if (strcmp("fullscreen-approved", aTopic) == 0) {
    nsCOMPtr<nsIDocument> subject(do_QueryInterface(aSubject));
    if (subject != this) {
      return NS_OK;
    }
    SetApprovedForFullscreen(true);
    if (gPendingPointerLockRequest) {
      // We have a request pending. Create a clone of it and re-dispatch so that
      // Run() method gets called again.
      nsCOMPtr<Element> el =
        do_QueryReferent(gPendingPointerLockRequest->mElement);
      nsCOMPtr<nsIDocument> doc =
        do_QueryReferent(gPendingPointerLockRequest->mDocument);
      bool userInputOrChromeCaller =
        gPendingPointerLockRequest->mUserInputOrChromeCaller;
      gPendingPointerLockRequest->Handled();
      if (doc == this && el && el->GetCurrentDoc() == doc) {
        nsPointerLockPermissionRequest* clone =
          new nsPointerLockPermissionRequest(el, userInputOrChromeCaller);
        gPendingPointerLockRequest = clone;
        nsCOMPtr<nsIRunnable> r = gPendingPointerLockRequest.get();
        NS_DispatchToMainThread(r);
      }
    }
  }
  return NS_OK;
}

void
nsDocument::RequestPointerLock(Element* aElement)
{
  NS_ASSERTION(aElement,
    "Must pass non-null element to nsDocument::RequestPointerLock");

  nsCOMPtr<Element> pointerLockedElement =
    do_QueryReferent(nsEventStateManager::sPointerLockedElement);
  if (aElement == pointerLockedElement) {
    DispatchPointerLockChange(this);
    return;
  }

  if (!ShouldLockPointer(aElement, pointerLockedElement)) {
    DispatchPointerLockError(this);
    return;
  }

  bool userInputOrChromeCaller = nsEventStateManager::IsHandlingUserInput() ||
                                 nsContentUtils::IsCallerChrome();

  gPendingPointerLockRequest =
    new nsPointerLockPermissionRequest(aElement, userInputOrChromeCaller);
  nsCOMPtr<nsIRunnable> r = gPendingPointerLockRequest.get();
  NS_DispatchToMainThread(r);
}

bool
nsDocument::ShouldLockPointer(Element* aElement, Element* aCurrentLock,
                              bool aNoFocusCheck)
{
  // Check if pointer lock pref is enabled
  if (!Preferences::GetBool("full-screen-api.pointer-lock.enabled")) {
    NS_WARNING("ShouldLockPointer(): Pointer Lock pref not enabled");
    return false;
  }

  if (aCurrentLock && aCurrentLock->OwnerDoc() != aElement->OwnerDoc()) {
    NS_WARNING("ShouldLockPointer(): Existing pointer lock element in a different document");
    return false;
  }

  if (!aElement->IsInDoc()) {
    NS_WARNING("ShouldLockPointer(): Element without Document");
    return false;
  }

  if (mSandboxFlags & SANDBOXED_POINTER_LOCK) {
    NS_WARNING("ShouldLockPointer(): Document is sandboxed and doesn't allow pointer-lock");
    return false;
  }

  // Check if the element is in a document with a docshell.
  nsCOMPtr<nsIDocument> ownerDoc = aElement->OwnerDoc();
  if (!nsCOMPtr<nsISupports>(ownerDoc->GetContainer())) {
    return false;
  }
  nsCOMPtr<nsPIDOMWindow> ownerWindow = ownerDoc->GetWindow();
  if (!ownerWindow) {
    return false;
  }
  nsCOMPtr<nsPIDOMWindow> ownerInnerWindow = ownerDoc->GetInnerWindow();
  if (!ownerInnerWindow) {
    return false;
  }
  if (ownerWindow->GetCurrentInnerWindow() != ownerInnerWindow) {
    return false;
  }

  nsCOMPtr<nsIDOMWindow> top;
  ownerWindow->GetScriptableTop(getter_AddRefs(top));
  nsCOMPtr<nsPIDOMWindow> piTop = do_QueryInterface(top);
  if (!piTop || !piTop->GetExtantDoc() ||
      piTop->GetExtantDoc()->Hidden()) {
    NS_WARNING("ShouldLockPointer(): Top document isn't visible.");
    return false;
  }

  if (!aNoFocusCheck) {
    mozilla::ErrorResult rv;
    if (!piTop->GetExtantDoc()->HasFocus(rv)) {
      NS_WARNING("ShouldLockPointer(): Top document isn't focused.");
      return false;
    }
  }

  return true;
}

bool
nsDocument::SetPointerLock(Element* aElement, int aCursorStyle)
{
  // NOTE: aElement will be nullptr when unlocking.
  nsCOMPtr<nsPIDOMWindow> window = GetWindow();
  if (!window) {
    NS_WARNING("SetPointerLock(): No Window");
    return false;
  }

  nsIDocShell *docShell = window->GetDocShell();
  if (!docShell) {
    NS_WARNING("SetPointerLock(): No DocShell (window already closed?)");
    return false;
  }

  nsRefPtr<nsPresContext> presContext;
  docShell->GetPresContext(getter_AddRefs(presContext));
  if (!presContext) {
    NS_WARNING("SetPointerLock(): Unable to get presContext in \
                domWindow->GetDocShell()->GetPresContext()");
    return false;
  }

  nsCOMPtr<nsIPresShell> shell = presContext->PresShell();
  if (!shell) {
    NS_WARNING("SetPointerLock(): Unable to find presContext->PresShell()");
    return false;
  }

  nsIFrame* rootFrame = shell->GetRootFrame();
  if (!rootFrame) {
    NS_WARNING("SetPointerLock(): Unable to get root frame");
    return false;
  }

  nsCOMPtr<nsIWidget> widget = rootFrame->GetNearestWidget();
  if (!widget) {
    NS_WARNING("SetPointerLock(): Unable to find widget in \
                shell->GetRootFrame()->GetNearestWidget();");
    return false;
  }

  if (aElement && (aElement->OwnerDoc() != this)) {
    NS_WARNING("SetPointerLock(): Element not in this document.");
    return false;
  }

  // Hide the cursor and set pointer lock for future mouse events
  nsRefPtr<nsEventStateManager> esm = presContext->EventStateManager();
  esm->SetCursor(aCursorStyle, nullptr, false,
                 0.0f, 0.0f, widget, true);
  esm->SetPointerLock(widget, aElement);

  return true;
}

void
nsDocument::UnlockPointer(nsIDocument* aDoc)
{
  if (!nsEventStateManager::sIsPointerLocked) {
    return;
  }

  nsCOMPtr<nsIDocument> pointerLockedDoc =
    do_QueryReferent(nsEventStateManager::sPointerLockedDoc);
  if (!pointerLockedDoc || (aDoc && aDoc != pointerLockedDoc)) {
    return;
  }
  nsDocument* doc = static_cast<nsDocument*>(pointerLockedDoc.get());
  if (!doc->SetPointerLock(nullptr, NS_STYLE_CURSOR_AUTO)) {
    return;
  }

  nsCOMPtr<Element> pointerLockedElement =
    do_QueryReferent(nsEventStateManager::sPointerLockedElement);
  if (pointerLockedElement) {
    pointerLockedElement->ClearPointerLock();
  }

  nsEventStateManager::sPointerLockedElement = nullptr;
  nsEventStateManager::sPointerLockedDoc = nullptr;
  static_cast<nsDocument*>(pointerLockedDoc.get())->mAllowRelocking = !!aDoc;
  gPendingPointerLockRequest = nullptr;
  DispatchPointerLockChange(pointerLockedDoc);
}

void
nsIDocument::UnlockPointer(nsIDocument* aDoc)
{
  nsDocument::UnlockPointer(aDoc);
}

NS_IMETHODIMP
nsDocument::MozExitPointerLock()
{
  nsIDocument::MozExitPointerLock();
  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetMozPointerLockElement(nsIDOMElement** aPointerLockedElement)
{
  Element* el = nsIDocument::GetMozPointerLockElement();
  nsCOMPtr<nsIDOMElement> retval = do_QueryInterface(el);
  retval.forget(aPointerLockedElement);
  return NS_OK;
}

Element*
nsIDocument::GetMozPointerLockElement()
{
  nsCOMPtr<Element> pointerLockedElement =
    do_QueryReferent(nsEventStateManager::sPointerLockedElement);
  if (!pointerLockedElement) {
    return nullptr;
  }

  // Make sure pointer locked element is in the same document and domain.
  nsCOMPtr<nsIDocument> pointerLockedDoc =
    do_QueryReferent(nsEventStateManager::sPointerLockedDoc);
  if (pointerLockedDoc != this) {
    return nullptr;
  }
  nsresult rv = nsContentUtils::CheckSameOrigin(this, pointerLockedElement);
  if (NS_FAILED(rv)) {
    return nullptr;
  }

  return pointerLockedElement;
}

void
nsDocument::XPCOMShutdown()
{
  gPendingPointerLockRequest = nullptr;
}

#define EVENT(name_, id_, type_, struct_)                                     \
  NS_IMETHODIMP nsDocument::GetOn##name_(JSContext *cx, JS::Value *vp) {      \
    return nsINode::GetOn##name_(cx, vp);                                     \
  }                                                                           \
  NS_IMETHODIMP nsDocument::SetOn##name_(JSContext *cx, const JS::Value &v) { \
    return nsINode::SetOn##name_(cx, v);                                      \
  }
#define DOCUMENT_ONLY_EVENT EVENT
#include "nsEventNameList.h"
#undef DOCUMENT_ONLY_EVENT
#undef EVENT

void
nsDocument::UpdateVisibilityState()
{
  dom::VisibilityState oldState = mVisibilityState;
  mVisibilityState = GetVisibilityState();
  if (oldState != mVisibilityState) {
    nsContentUtils::DispatchTrustedEvent(this, static_cast<nsIDocument*>(this),
                                         NS_LITERAL_STRING("visibilitychange"),
                                         /* bubbles = */ true,
                                         /* cancelable = */ false);
    nsContentUtils::DispatchTrustedEvent(this, static_cast<nsIDocument*>(this),
                                         NS_LITERAL_STRING("mozvisibilitychange"),
                                         /* bubbles = */ true,
                                         /* cancelable = */ false);

    EnumerateFreezableElements(NotifyActivityChanged, nullptr);
  }
}

VisibilityState
nsDocument::GetVisibilityState() const
{
  // We have to check a few pieces of information here:
  // 1)  Are we in bfcache (!IsVisible())?  If so, nothing else matters.
  // 2)  Do we have an outer window?  If not, we're hidden.  Note that we don't
  //     want to use GetWindow here because it does weird groveling for windows
  //     in some cases.
  // 3)  Is our outer window background?  If so, we're hidden.
  // Otherwise, we're visible.
  if (!IsVisible() || !mWindow || !mWindow->GetOuterWindow() ||
      mWindow->GetOuterWindow()->IsBackground()) {
    return dom::VisibilityState::Hidden;
  }

  return dom::VisibilityState::Visible;
}

/* virtual */ void
nsDocument::PostVisibilityUpdateEvent()
{
  nsCOMPtr<nsIRunnable> event =
    NS_NewRunnableMethod(this, &nsDocument::UpdateVisibilityState);
  NS_DispatchToMainThread(event);
}

NS_IMETHODIMP
nsDocument::GetMozHidden(bool* aHidden)
{
  *aHidden = MozHidden();
  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetHidden(bool* aHidden)
{
  *aHidden = Hidden();
  return NS_OK;
}

NS_IMETHODIMP
nsDocument::GetMozVisibilityState(nsAString& aState)
{
  WarnOnceAbout(ePrefixedVisibilityAPI);
  return GetVisibilityState(aState);
}

NS_IMETHODIMP
nsDocument::GetVisibilityState(nsAString& aState)
{
  const EnumEntry& entry =
    VisibilityStateValues::strings[static_cast<int>(mVisibilityState)];
  aState.AssignASCII(entry.value, entry.length);
  return NS_OK;
}

/* virtual */ void
nsIDocument::DocSizeOfExcludingThis(nsWindowSizes* aWindowSizes) const
{
  aWindowSizes->mDOMOther +=
    nsINode::SizeOfExcludingThis(aWindowSizes->mMallocSizeOf);

  if (mPresShell) {
    mPresShell->SizeOfIncludingThis(aWindowSizes->mMallocSizeOf,
                                    &aWindowSizes->mArenaStats,
                                    &aWindowSizes->mLayoutPresShell,
                                    &aWindowSizes->mLayoutStyleSets,
                                    &aWindowSizes->mLayoutTextRuns,
                                    &aWindowSizes->mLayoutPresContext);
  }

  aWindowSizes->mPropertyTables +=
    mPropertyTable.SizeOfExcludingThis(aWindowSizes->mMallocSizeOf);
  for (uint32_t i = 0, count = mExtraPropertyTables.Length();
       i < count; ++i) {
    aWindowSizes->mPropertyTables +=
      mExtraPropertyTables[i]->SizeOfExcludingThis(aWindowSizes->mMallocSizeOf);
  }

  // Measurement of the following members may be added later if DMD finds it
  // is worthwhile:
  // - many!
}

void
nsIDocument::DocSizeOfIncludingThis(nsWindowSizes* aWindowSizes) const
{
  aWindowSizes->mDOMOther += aWindowSizes->mMallocSizeOf(this);
  DocSizeOfExcludingThis(aWindowSizes);
}

static size_t
SizeOfStyleSheetsElementIncludingThis(nsIStyleSheet* aStyleSheet,
                                      MallocSizeOf aMallocSizeOf,
                                      void* aData)
{
  return aStyleSheet->SizeOfIncludingThis(aMallocSizeOf);
}

size_t
nsDocument::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
{
  // This SizeOfExcludingThis() overrides the one from nsINode.  But
  // nsDocuments can only appear at the top of the DOM tree, and we use the
  // specialized DocSizeOfExcludingThis() in that case.  So this should never
  // be called.
  MOZ_CRASH();
}

void
nsDocument::DocSizeOfExcludingThis(nsWindowSizes* aWindowSizes) const
{
  nsIDocument::DocSizeOfExcludingThis(aWindowSizes);

  for (nsIContent* node = nsINode::GetFirstChild();
       node;
       node = node->GetNextNode(this))
  {
    size_t nodeSize = node->SizeOfIncludingThis(aWindowSizes->mMallocSizeOf);
    size_t* p;

    switch (node->NodeType()) {
    case nsIDOMNode::ELEMENT_NODE:
      p = &aWindowSizes->mDOMElementNodes;
      break;
    case nsIDOMNode::TEXT_NODE:
      p = &aWindowSizes->mDOMTextNodes;
      break;
    case nsIDOMNode::CDATA_SECTION_NODE:
      p = &aWindowSizes->mDOMCDATANodes;
      break;
    case nsIDOMNode::COMMENT_NODE:
      p = &aWindowSizes->mDOMCommentNodes;
      break;
    default:
      p = &aWindowSizes->mDOMOther;
      break;
    }

    *p += nodeSize;
  }

  aWindowSizes->mStyleSheets +=
    mStyleSheets.SizeOfExcludingThis(SizeOfStyleSheetsElementIncludingThis,
                                     aWindowSizes->mMallocSizeOf);
  aWindowSizes->mStyleSheets +=
    mCatalogSheets.SizeOfExcludingThis(SizeOfStyleSheetsElementIncludingThis,
                                       aWindowSizes->mMallocSizeOf);
  aWindowSizes->mStyleSheets +=
    mAdditionalSheets[eAgentSheet].
      SizeOfExcludingThis(SizeOfStyleSheetsElementIncludingThis,
                          aWindowSizes->mMallocSizeOf);
  aWindowSizes->mStyleSheets +=
    mAdditionalSheets[eUserSheet].
      SizeOfExcludingThis(SizeOfStyleSheetsElementIncludingThis,
                          aWindowSizes->mMallocSizeOf);
  aWindowSizes->mStyleSheets +=
    mAdditionalSheets[eAuthorSheet].
      SizeOfExcludingThis(SizeOfStyleSheetsElementIncludingThis,
                          aWindowSizes->mMallocSizeOf);
  // Lumping in the loader with the style-sheets size is not ideal,
  // but most of the things in there are in fact stylesheets, so it
  // doesn't seem worthwhile to separate it out.
  aWindowSizes->mStyleSheets +=
    CSSLoader()->SizeOfIncludingThis(aWindowSizes->mMallocSizeOf);

  aWindowSizes->mDOMOther +=
    mAttrStyleSheet ?
    mAttrStyleSheet->DOMSizeOfIncludingThis(aWindowSizes->mMallocSizeOf) :
    0;

  aWindowSizes->mDOMOther +=
    mStyledLinks.SizeOfExcludingThis(nullptr, aWindowSizes->mMallocSizeOf);

  aWindowSizes->mDOMOther +=
    mIdentifierMap.SizeOfExcludingThis(nsIdentifierMapEntry::SizeOfExcludingThis,
                                       aWindowSizes->mMallocSizeOf);

  // Measurement of the following members may be added later if DMD finds it
  // is worthwhile:
  // - many!
}

NS_IMETHODIMP
nsDocument::QuerySelector(const nsAString& aSelector, nsIDOMElement **aReturn)
{
  return nsINode::QuerySelector(aSelector, aReturn);
}

NS_IMETHODIMP
nsDocument::QuerySelectorAll(const nsAString& aSelector, nsIDOMNodeList **aReturn)
{
  return nsINode::QuerySelectorAll(aSelector, aReturn);
}

already_AddRefed<nsIDocument>
nsIDocument::Constructor(const GlobalObject& aGlobal, ErrorResult& rv)
{
  nsCOMPtr<nsIScriptGlobalObject> global = do_QueryInterface(aGlobal.Get());
  if (!global) {
    rv.Throw(NS_ERROR_UNEXPECTED);
    return nullptr;
  }

  nsCOMPtr<nsIScriptObjectPrincipal> prin = do_QueryInterface(aGlobal.Get());
  if (!prin) {
    rv.Throw(NS_ERROR_UNEXPECTED);
    return nullptr;
  }

  nsCOMPtr<nsIURI> uri;
  NS_NewURI(getter_AddRefs(uri), "about:blank");
  if (!uri) {
    rv.Throw(NS_ERROR_OUT_OF_MEMORY);
    return nullptr;
  }

  nsCOMPtr<nsIDOMDocument> document;
  nsresult res =
    NS_NewDOMDocument(getter_AddRefs(document),
                      NullString(),
                      EmptyString(),
                      nullptr,
                      uri,
                      uri,
                      prin->GetPrincipal(),
                      true,
                      global,
                      DocumentFlavorLegacyGuess);
  if (NS_FAILED(res)) {
    rv.Throw(res);
    return nullptr;
  }

  nsCOMPtr<nsIDocument> doc = do_QueryInterface(document);
  doc->SetReadyStateInternal(nsIDocument::READYSTATE_COMPLETE);

  return doc.forget();
}

already_AddRefed<nsIDOMXPathExpression>
nsIDocument::CreateExpression(const nsAString& aExpression,
                              nsIDOMXPathNSResolver* aResolver,
                              ErrorResult& rv)
{
  nsCOMPtr<nsIDOMXPathEvaluator> evaluator = do_QueryInterface(this);
  if (!evaluator) {
    rv.Throw(NS_ERROR_FAILURE);
    return nullptr;
  }

  nsCOMPtr<nsIDOMXPathExpression> expr;
  rv = evaluator->CreateExpression(aExpression, aResolver, getter_AddRefs(expr));
  return expr.forget();
}

already_AddRefed<nsIDOMXPathNSResolver>
nsIDocument::CreateNSResolver(nsINode* aNodeResolver,
                              ErrorResult& rv)
{
  nsCOMPtr<nsIDOMXPathEvaluator> evaluator = do_QueryInterface(this);
  if (!evaluator) {
    rv.Throw(NS_ERROR_FAILURE);
    return nullptr;
  }

  nsCOMPtr<nsIDOMNode> nodeResolver = do_QueryInterface(aNodeResolver);
  nsCOMPtr<nsIDOMXPathNSResolver> res;
  rv = evaluator->CreateNSResolver(nodeResolver, getter_AddRefs(res));
  return res.forget();
}

already_AddRefed<nsISupports>
nsIDocument::Evaluate(const nsAString& aExpression, nsINode* aContextNode,
                      nsIDOMXPathNSResolver* aResolver, uint16_t aType,
                      nsISupports* aResult, ErrorResult& rv)
{
  nsCOMPtr<nsIDOMXPathEvaluator> evaluator = do_QueryInterface(this);
  if (!evaluator) {
    rv.Throw(NS_ERROR_FAILURE);
    return nullptr;
  }

  nsCOMPtr<nsIDOMNode> contextNode = do_QueryInterface(aContextNode);
  nsCOMPtr<nsISupports> res;
  rv = evaluator->Evaluate(aExpression, contextNode, aResolver, aType,
                           aResult, getter_AddRefs(res));
  return res.forget();
}

// This is just a hack around the fact that window.document is not
// [Unforgeable] yet.
JSObject*
nsIDocument::WrapObject(JSContext *aCx, JS::Handle<JSObject*> aScope)
{
  MOZ_ASSERT(IsDOMBinding());

  JS::Rooted<JSObject*> obj(aCx, nsINode::WrapObject(aCx, aScope));
  if (!obj) {
    return nullptr;
  }

  nsCOMPtr<nsPIDOMWindow> win = do_QueryInterface(GetInnerWindow());
  if (!win) {
    // No window, nothing else to do here
    return obj;
  }

  if (this != win->GetExtantDoc()) {
    // We're not the current document; we're also done here
    return obj;
  }

  JSAutoCompartment ac(aCx, obj);

  JS::Rooted<JS::Value> winVal(aCx);
  nsCOMPtr<nsIXPConnectJSObjectHolder> holder;
  nsresult rv = nsContentUtils::WrapNative(aCx, obj, win,
                                           &NS_GET_IID(nsIDOMWindow),
                                           winVal.address(),
                                           getter_AddRefs(holder),
                                           false);
  if (NS_FAILED(rv)) {
    Throw<true>(aCx, rv);
    return nullptr;
  }

  NS_NAMED_LITERAL_STRING(doc_str, "document");

  if (!JS_DefineUCProperty(aCx, JSVAL_TO_OBJECT(winVal),
                           reinterpret_cast<const jschar *>
                                           (doc_str.get()),
                           doc_str.Length(), JS::ObjectValue(*obj),
                           JS_PropertyStub, JS_StrictPropertyStub,
                           JSPROP_READONLY | JSPROP_ENUMERATE)) {
    return nullptr;
  }

  return obj;
}

bool
MarkDocumentTreeToBeInSyncOperation(nsIDocument* aDoc, void* aData)
{
  nsCOMArray<nsIDocument>* documents =
    static_cast<nsCOMArray<nsIDocument>*>(aData);
  if (aDoc) {
    aDoc->SetIsInSyncOperation(true);
    documents->AppendObject(aDoc);
    aDoc->EnumerateSubDocuments(MarkDocumentTreeToBeInSyncOperation, aData);
  }
  return true;
}

nsAutoSyncOperation::nsAutoSyncOperation(nsIDocument* aDoc)
{
  mMicroTaskLevel = nsContentUtils::MicroTaskLevel();
  nsContentUtils::SetMicroTaskLevel(0);
  if (aDoc) {
    nsPIDOMWindow* win = aDoc->GetWindow();
    if (win) {
      nsCOMPtr<nsIDOMWindow> topWindow;
      win->GetTop(getter_AddRefs(topWindow));
      nsCOMPtr<nsPIDOMWindow> top = do_QueryInterface(topWindow);
      if (top) {
        nsCOMPtr<nsIDocument> doc = top->GetExtantDoc();
        MarkDocumentTreeToBeInSyncOperation(doc, &mDocuments);
      }
    }
  }
}

nsAutoSyncOperation::~nsAutoSyncOperation()
{
  for (int32_t i = 0; i < mDocuments.Count(); ++i) {
    mDocuments[i]->SetIsInSyncOperation(false);
  }
  nsContentUtils::SetMicroTaskLevel(mMicroTaskLevel);
}
