gecko-dev/dom/xul/XULDocument.h

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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* 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/. */
#ifndef mozilla_dom_XULDocument_h
#define mozilla_dom_XULDocument_h
#include "nsCOMPtr.h"
#include "nsXULPrototypeDocument.h"
#include "nsXULPrototypeCache.h"
#include "nsTArray.h"
#include "mozilla/dom/XMLDocument.h"
#include "mozilla/StyleSheetHandle.h"
#include "nsForwardReference.h"
#include "nsIContent.h"
#include "nsIDOMXULCommandDispatcher.h"
#include "nsIDOMXULDocument.h"
#include "nsCOMArray.h"
#include "nsIURI.h"
#include "nsIXULDocument.h"
#include "nsScriptLoader.h"
#include "nsIStreamListener.h"
#include "nsIStreamLoader.h"
#include "nsICSSLoaderObserver.h"
#include "nsIXULStore.h"
#include "mozilla/Attributes.h"
#include "js/TracingAPI.h"
#include "js/TypeDecls.h"
class nsIRDFResource;
class nsIRDFService;
class nsPIWindowRoot;
#if 0 // XXXbe save me, scc (need NSCAP_FORWARD_DECL(nsXULPrototypeScript))
class nsIObjectInputStream;
class nsIObjectOutputStream;
#else
#include "nsIObjectInputStream.h"
#include "nsIObjectOutputStream.h"
#include "nsXULElement.h"
#endif
#include "nsURIHashKey.h"
#include "nsInterfaceHashtable.h"
class nsRefMapEntry : public nsStringHashKey
{
public:
explicit nsRefMapEntry(const nsAString& aKey) :
nsStringHashKey(&aKey)
{
}
explicit nsRefMapEntry(const nsAString* aKey) :
nsStringHashKey(aKey)
{
}
nsRefMapEntry(const nsRefMapEntry& aOther) :
nsStringHashKey(&aOther.GetKey())
{
NS_ERROR("Should never be called");
}
mozilla::dom::Element* GetFirstElement();
void AppendAll(nsCOMArray<nsIContent>* aElements);
/**
* @return true if aElement was added, false if we failed due to OOM
*/
bool AddElement(mozilla::dom::Element* aElement);
/**
* @return true if aElement was removed and it was the last content for
* this ref, so this entry should be removed from the map
*/
bool RemoveElement(mozilla::dom::Element* aElement);
private:
nsTArray<mozilla::dom::Element*> mRefContentList;
};
/**
* The XUL document class
*/
namespace mozilla {
namespace dom {
class XULDocument final : public XMLDocument,
public nsIXULDocument,
public nsIDOMXULDocument,
public nsIStreamLoaderObserver,
public nsICSSLoaderObserver,
public nsIOffThreadScriptReceiver
{
public:
XULDocument();
// nsISupports interface
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_NSISTREAMLOADEROBSERVER
// nsIDocument interface
virtual void Reset(nsIChannel* aChannel, nsILoadGroup* aLoadGroup) override;
virtual void ResetToURI(nsIURI *aURI, nsILoadGroup* aLoadGroup,
nsIPrincipal* aPrincipal) override;
virtual nsresult StartDocumentLoad(const char* aCommand,
nsIChannel *channel,
nsILoadGroup* aLoadGroup,
nsISupports* aContainer,
nsIStreamListener **aDocListener,
bool aReset = true,
nsIContentSink* aSink = nullptr) override;
virtual void SetContentType(const nsAString& aContentType) override;
virtual void EndLoad() override;
// nsIMutationObserver interface
NS_DECL_NSIMUTATIONOBSERVER_CONTENTAPPENDED
NS_DECL_NSIMUTATIONOBSERVER_CONTENTINSERTED
NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED
NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED
NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTEWILLCHANGE
// nsIXULDocument interface
virtual void GetElementsForID(const nsAString& aID,
nsCOMArray<nsIContent>& aElements) override;
NS_IMETHOD AddSubtreeToDocument(nsIContent* aContent) override;
NS_IMETHOD RemoveSubtreeFromDocument(nsIContent* aContent) override;
NS_IMETHOD SetTemplateBuilderFor(nsIContent* aContent,
nsIXULTemplateBuilder* aBuilder) override;
NS_IMETHOD GetTemplateBuilderFor(nsIContent* aContent,
nsIXULTemplateBuilder** aResult) override;
NS_IMETHOD OnPrototypeLoadDone(bool aResumeWalk) override;
bool OnDocumentParserError() override;
// nsINode interface overrides
virtual nsresult Clone(mozilla::dom::NodeInfo *aNodeInfo, nsINode **aResult) const override;
// nsIDOMNode interface
NS_FORWARD_NSIDOMNODE_TO_NSINODE
// nsIDOMDocument interface
using nsDocument::CreateElement;
using nsDocument::CreateElementNS;
NS_FORWARD_NSIDOMDOCUMENT(XMLDocument::)
// And explicitly import the things from nsDocument that we just shadowed
using nsDocument::GetImplementation;
using nsDocument::GetTitle;
using nsDocument::SetTitle;
using nsDocument::GetLastStyleSheetSet;
using nsDocument::MozSetImageElement;
using nsDocument::GetMozFullScreenElement;
using nsIDocument::GetLocation;
// nsDocument interface overrides
virtual Element* GetElementById(const nsAString & elementId) override;
// nsIDOMXULDocument interface
NS_DECL_NSIDOMXULDOCUMENT
// nsICSSLoaderObserver
NS_IMETHOD StyleSheetLoaded(mozilla::StyleSheetHandle aSheet,
bool aWasAlternate,
nsresult aStatus) override;
virtual void EndUpdate(nsUpdateType aUpdateType) override;
virtual bool IsDocumentRightToLeft() override;
virtual void ResetDocumentDirection() override;
virtual int GetDocumentLWTheme() override;
virtual void ResetDocumentLWTheme() override { mDocLWTheme = Doc_Theme_Uninitialized; }
NS_IMETHOD OnScriptCompileComplete(JSScript* aScript, nsresult aStatus) override;
static bool
MatchAttribute(nsIContent* aContent,
int32_t aNameSpaceID,
nsIAtom* aAttrName,
void* aData);
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(XULDocument, XMLDocument)
void TraceProtos(JSTracer* aTrc, uint32_t aGCNumber);
// WebIDL API
already_AddRefed<nsINode> GetPopupNode();
void SetPopupNode(nsINode* aNode);
already_AddRefed<nsINode> GetPopupRangeParent(ErrorResult& aRv);
int32_t GetPopupRangeOffset(ErrorResult& aRv);
already_AddRefed<nsINode> GetTooltipNode();
void SetTooltipNode(nsINode* aNode) { /* do nothing */ }
nsIDOMXULCommandDispatcher* GetCommandDispatcher() const
{
return mCommandDispatcher;
}
int32_t GetWidth(ErrorResult& aRv);
int32_t GetHeight(ErrorResult& aRv);
already_AddRefed<nsINodeList>
GetElementsByAttribute(const nsAString& aAttribute,
const nsAString& aValue);
already_AddRefed<nsINodeList>
GetElementsByAttributeNS(const nsAString& aNamespaceURI,
const nsAString& aAttribute,
const nsAString& aValue,
ErrorResult& aRv);
void AddBroadcastListenerFor(Element& aBroadcaster, Element& aListener,
const nsAString& aAttr, ErrorResult& aRv);
void RemoveBroadcastListenerFor(Element& aBroadcaster, Element& aListener,
const nsAString& aAttr);
void Persist(const nsAString& aId, const nsAString& aAttr, ErrorResult& aRv)
{
aRv = Persist(aId, aAttr);
}
using nsDocument::GetBoxObjectFor;
void LoadOverlay(const nsAString& aURL, nsIObserver* aObserver,
ErrorResult& aRv)
{
aRv = LoadOverlay(aURL, aObserver);
}
protected:
virtual ~XULDocument();
// Implementation methods
friend nsresult
(::NS_NewXULDocument(nsIXULDocument** aResult));
nsresult Init(void) override;
nsresult StartLayout(void);
nsresult
AddElementToRefMap(Element* aElement);
void
RemoveElementFromRefMap(Element* aElement);
nsresult GetViewportSize(int32_t* aWidth, int32_t* aHeight);
nsresult PrepareToLoad(nsISupports* aContainer,
const char* aCommand,
nsIChannel* aChannel,
nsILoadGroup* aLoadGroup,
nsIParser** aResult);
nsresult
PrepareToLoadPrototype(nsIURI* aURI,
const char* aCommand,
nsIPrincipal* aDocumentPrincipal,
nsIParser** aResult);
nsresult
LoadOverlayInternal(nsIURI* aURI, bool aIsDynamic, bool* aShouldReturn,
bool* aFailureFromContent);
nsresult ApplyPersistentAttributes();
nsresult ApplyPersistentAttributesInternal();
nsresult ApplyPersistentAttributesToElements(const nsAString &aID,
nsCOMArray<nsIContent>& aElements);
nsresult
AddElementToDocumentPre(Element* aElement);
nsresult
AddElementToDocumentPost(Element* aElement);
nsresult
ExecuteOnBroadcastHandlerFor(Element* aBroadcaster,
Element* aListener,
nsIAtom* aAttr);
nsresult
BroadcastAttributeChangeFromOverlay(nsIContent* aNode,
int32_t aNameSpaceID,
nsIAtom* aAttribute,
nsIAtom* aPrefix,
const nsAString& aValue);
already_AddRefed<nsPIWindowRoot> GetWindowRoot();
static void DirectionChanged(const char* aPrefName, void* aData);
// pseudo constants
static int32_t gRefCnt;
static nsIAtom** kIdentityAttrs[];
static nsIRDFService* gRDFService;
static nsIRDFResource* kNC_persist;
static nsIRDFResource* kNC_attribute;
static nsIRDFResource* kNC_value;
static LazyLogModule gXULLog;
nsresult
Persist(nsIContent* aElement, int32_t aNameSpaceID, nsIAtom* aAttribute);
// Just like Persist but ignores the return value so we can use it
// as a runnable method.
void DoPersist(nsIContent* aElement, int32_t aNameSpaceID, nsIAtom* aAttribute)
{
Persist(aElement, aNameSpaceID, aAttribute);
}
virtual JSObject* WrapNode(JSContext *aCx, JS::Handle<JSObject*> aGivenProto) override;
// IMPORTANT: The ownership implicit in the following member
// variables has been explicitly checked and set using nsCOMPtr
// for owning pointers and raw COM interface pointers for weak
// (ie, non owning) references. If you add any members to this
// class, please make the ownership explicit (pinkerton, scc).
// NOTE, THIS IS STILL IN PROGRESS, TALK TO PINK OR SCC BEFORE
// CHANGING
XULDocument* mNextSrcLoadWaiter; // [OWNER] but not COMPtr
// Tracks elements with a 'ref' attribute, or an 'id' attribute where
// the element's namespace has no registered ID attribute name.
nsTHashtable<nsRefMapEntry> mRefMap;
nsCOMPtr<nsIXULStore> mLocalStore;
bool mApplyingPersistedAttrs;
bool mIsWritingFastLoad;
bool mDocumentLoaded;
/**
* Since ResumeWalk is interruptible, it's possible that last
* stylesheet finishes loading while the PD walk is still in
* progress (waiting for an overlay to finish loading).
* mStillWalking prevents DoneLoading (and StartLayout) from being
* called in this situation.
*/
bool mStillWalking;
/**
* These two values control where persistent attributes get applied.
*/
bool mRestrictPersistence;
nsTHashtable<nsStringHashKey> mPersistenceIds;
/**
* An array of style sheets, that will be added (preserving order) to the
* document after all of them are loaded (in DoneWalking).
*/
nsTArray<StyleSheetHandle::RefPtr> mOverlaySheets;
nsCOMPtr<nsIDOMXULCommandDispatcher> mCommandDispatcher; // [OWNER] of the focus tracker
// Maintains the template builders that have been attached to
// content elements
typedef nsInterfaceHashtable<nsISupportsHashKey, nsIXULTemplateBuilder>
BuilderTable;
BuilderTable* mTemplateBuilderTable;
uint32_t mPendingSheets;
/**
* document lightweight theme for use with :-moz-lwtheme, :-moz-lwtheme-brighttext
* and :-moz-lwtheme-darktext
*/
DocumentTheme mDocLWTheme;
/**
* Context stack, which maintains the state of the Builder and allows
* it to be interrupted.
*/
class ContextStack {
protected:
struct Entry {
nsXULPrototypeElement* mPrototype;
nsIContent* mElement;
int32_t mIndex;
Entry* mNext;
};
Entry* mTop;
int32_t mDepth;
public:
ContextStack();
~ContextStack();
int32_t Depth() { return mDepth; }
nsresult Push(nsXULPrototypeElement* aPrototype, nsIContent* aElement);
nsresult Pop();
nsresult Peek(nsXULPrototypeElement** aPrototype, nsIContent** aElement, int32_t* aIndex);
nsresult SetTopIndex(int32_t aIndex);
};
friend class ContextStack;
ContextStack mContextStack;
enum State { eState_Master, eState_Overlay };
State mState;
/**
* An array of overlay nsIURIs that have yet to be resolved. The
* order of the array is significant: overlays at the _end_ of the
* array are resolved before overlays earlier in the array (i.e.,
* it is a stack).
*
* In the current implementation the order the overlays are loaded
* in is as follows: first overlays from xul-overlay PIs, in the
* same order as in the document, then the overlays from the chrome
* registry.
*/
nsTArray<nsCOMPtr<nsIURI> > mUnloadedOverlays;
/**
* Load the transcluded script at the specified URI. If the
* prototype construction must 'block' until the load has
* completed, aBlock will be set to true.
*/
nsresult LoadScript(nsXULPrototypeScript *aScriptProto, bool* aBlock);
/**
* Execute the precompiled script object scoped by this XUL document's
* containing window object.
*/
nsresult ExecuteScript(nsXULPrototypeScript *aScript);
/**
* Create a delegate content model element from a prototype.
* Note that the resulting content node is not bound to any tree
*/
nsresult CreateElementFromPrototype(nsXULPrototypeElement* aPrototype,
Element** aResult,
bool aIsRoot);
/**
* Create a hook-up element to which content nodes can be attached for
* later resolution.
*/
nsresult CreateOverlayElement(nsXULPrototypeElement* aPrototype,
Element** aResult);
/**
* Add attributes from the prototype to the element.
*/
nsresult AddAttributes(nsXULPrototypeElement* aPrototype, nsIContent* aElement);
/**
* The prototype-script of the current transcluded script that is being
* loaded. For document.write('<script src="nestedwrite.js"><\/script>')
* to work, these need to be in a stack element type, and we need to hold
* the top of stack here.
*/
nsXULPrototypeScript* mCurrentScriptProto;
/**
* Whether the current transcluded script is being compiled off thread.
* The load event is blocked while this is in progress.
*/
bool mOffThreadCompiling;
/**
* If the current transcluded script is being compiled off thread, the
* source for that script.
*/
char16_t* mOffThreadCompileStringBuf;
size_t mOffThreadCompileStringLength;
/**
* Check if a XUL template builder has already been hooked up.
*/
static nsresult
CheckTemplateBuilderHookup(nsIContent* aElement, bool* aNeedsHookup);
/**
* Create a XUL template builder on the specified node.
*/
static nsresult
CreateTemplateBuilder(nsIContent* aElement);
/**
* Add the current prototype's style sheets (currently it's just
* style overlays from the chrome registry) to the document.
*/
nsresult AddPrototypeSheets();
protected:
/* Declarations related to forward references.
*
* Forward references are declarations which are added to the temporary
* list (mForwardReferences) during the document (or overlay) load and
* are resolved later, when the document loading is almost complete.
*/
/**
* The list of different types of forward references to resolve. After
* a reference is resolved, it is removed from this array (and
* automatically deleted)
*/
nsTArray<nsAutoPtr<nsForwardReference> > mForwardReferences;
/** Indicates what kind of forward references are still to be processed. */
nsForwardReference::Phase mResolutionPhase;
/**
* Adds aRef to the mForwardReferences array. Takes the ownership of aRef.
*/
nsresult AddForwardReference(nsForwardReference* aRef);
/**
* Resolve all of the document's forward references.
*/
nsresult ResolveForwardReferences();
/**
* Used to resolve broadcaster references
*/
class BroadcasterHookup : public nsForwardReference
{
protected:
XULDocument* mDocument; // [WEAK]
RefPtr<Element> mObservesElement; // [OWNER]
bool mResolved;
public:
BroadcasterHookup(XULDocument* aDocument,
Element* aObservesElement)
: mDocument(aDocument),
mObservesElement(aObservesElement),
mResolved(false)
{
}
virtual ~BroadcasterHookup();
virtual Phase GetPhase() override { return eHookup; }
virtual Result Resolve() override;
};
friend class BroadcasterHookup;
/**
* Used to hook up overlays
*/
class OverlayForwardReference : public nsForwardReference
{
protected:
XULDocument* mDocument; // [WEAK]
nsCOMPtr<nsIContent> mOverlay; // [OWNER]
bool mResolved;
nsresult Merge(nsIContent* aTargetNode, nsIContent* aOverlayNode, bool aNotify);
public:
OverlayForwardReference(XULDocument* aDocument, nsIContent* aOverlay)
: mDocument(aDocument), mOverlay(aOverlay), mResolved(false) {}
virtual ~OverlayForwardReference();
virtual Phase GetPhase() override { return eConstruction; }
virtual Result Resolve() override;
};
friend class OverlayForwardReference;
class TemplateBuilderHookup : public nsForwardReference
{
protected:
nsCOMPtr<nsIContent> mElement; // [OWNER]
public:
explicit TemplateBuilderHookup(nsIContent* aElement)
: mElement(aElement) {}
virtual Phase GetPhase() override { return eHookup; }
virtual Result Resolve() override;
};
friend class TemplateBuilderHookup;
// The out params of FindBroadcaster only have values that make sense when
// the method returns NS_FINDBROADCASTER_FOUND. In all other cases, the
// values of the out params should not be relied on (though *aListener and
// *aBroadcaster do need to be released if non-null, of course).
nsresult
FindBroadcaster(Element* aElement,
Element** aListener,
nsString& aBroadcasterID,
nsString& aAttribute,
Element** aBroadcaster);
nsresult
CheckBroadcasterHookup(Element* aElement,
bool* aNeedsHookup,
bool* aDidResolve);
void
SynchronizeBroadcastListener(Element *aBroadcaster,
Element *aListener,
const nsAString &aAttr);
static
nsresult
InsertElement(nsINode* aParent, nsIContent* aChild, bool aNotify);
static
nsresult
RemoveElement(nsINode* aParent, nsINode* aChild);
/**
* The current prototype that we are walking to construct the
* content model.
*/
RefPtr<nsXULPrototypeDocument> mCurrentPrototype;
/**
* The master document (outermost, .xul) prototype, from which
* all subdocuments get their security principals.
*/
RefPtr<nsXULPrototypeDocument> mMasterPrototype;
/**
* Owning references to all of the prototype documents that were
* used to construct this document.
*/
nsTArray< RefPtr<nsXULPrototypeDocument> > mPrototypes;
/**
* Prepare to walk the current prototype.
*/
nsresult PrepareToWalk();
/**
* Creates a processing instruction based on aProtoPI and inserts
* it to the DOM (as the aIndex-th child of aParent).
*/
nsresult
CreateAndInsertPI(const nsXULPrototypePI* aProtoPI,
nsINode* aParent, uint32_t aIndex);
/**
* Inserts the passed <?xml-stylesheet ?> PI at the specified
* index. Loads and applies the associated stylesheet
* asynchronously.
* The prototype document walk can happen before the stylesheets
* are loaded, but the final steps in the load process (see
* DoneWalking()) are not run before all the stylesheets are done
* loading.
*/
nsresult
InsertXMLStylesheetPI(const nsXULPrototypePI* aProtoPI,
nsINode* aParent,
uint32_t aIndex,
nsIContent* aPINode);
/**
* Inserts the passed <?xul-overlay ?> PI at the specified index.
* Schedules the referenced overlay URI for further processing.
*/
nsresult
InsertXULOverlayPI(const nsXULPrototypePI* aProtoPI,
nsINode* aParent,
uint32_t aIndex,
nsIContent* aPINode);
/**
* Add overlays from the chrome registry to the set of unprocessed
* overlays still to do.
*/
nsresult AddChromeOverlays();
/**
* Resume (or initiate) an interrupted (or newly prepared)
* prototype walk.
*/
nsresult ResumeWalk();
/**
* Called at the end of ResumeWalk() and from StyleSheetLoaded().
* Expects that both the prototype document walk is complete and
* all referenced stylesheets finished loading.
*/
nsresult DoneWalking();
/**
* Report that an overlay failed to load
* @param aURI the URI of the overlay that failed to load
*/
void ReportMissingOverlay(nsIURI* aURI);
class CachedChromeStreamListener : public nsIStreamListener {
protected:
RefPtr<XULDocument> mDocument;
bool mProtoLoaded;
virtual ~CachedChromeStreamListener();
public:
CachedChromeStreamListener(XULDocument* aDocument,
bool aProtoLoaded);
NS_DECL_ISUPPORTS
NS_DECL_NSIREQUESTOBSERVER
NS_DECL_NSISTREAMLISTENER
};
friend class CachedChromeStreamListener;
class ParserObserver : public nsIRequestObserver {
protected:
RefPtr<XULDocument> mDocument;
RefPtr<nsXULPrototypeDocument> mPrototype;
virtual ~ParserObserver();
public:
ParserObserver(XULDocument* aDocument,
nsXULPrototypeDocument* aPrototype);
NS_DECL_ISUPPORTS
NS_DECL_NSIREQUESTOBSERVER
};
friend class ParserObserver;
/**
* A map from a broadcaster element to a list of listener elements.
*/
PLDHashTable* mBroadcasterMap;
nsAutoPtr<nsInterfaceHashtable<nsURIHashKey,nsIObserver> > mOverlayLoadObservers;
nsAutoPtr<nsInterfaceHashtable<nsURIHashKey,nsIObserver> > mPendingOverlayLoadNotifications;
bool mInitialLayoutComplete;
class nsDelayedBroadcastUpdate
{
public:
nsDelayedBroadcastUpdate(Element* aBroadcaster,
Element* aListener,
const nsAString &aAttr)
: mBroadcaster(aBroadcaster), mListener(aListener), mAttr(aAttr),
mSetAttr(false), mNeedsAttrChange(false) {}
nsDelayedBroadcastUpdate(Element* aBroadcaster,
Element* aListener,
nsIAtom* aAttrName,
const nsAString &aAttr,
bool aSetAttr,
bool aNeedsAttrChange)
: mBroadcaster(aBroadcaster), mListener(aListener), mAttr(aAttr),
mAttrName(aAttrName), mSetAttr(aSetAttr),
mNeedsAttrChange(aNeedsAttrChange) {}
nsDelayedBroadcastUpdate(const nsDelayedBroadcastUpdate& aOther)
: mBroadcaster(aOther.mBroadcaster), mListener(aOther.mListener),
mAttr(aOther.mAttr), mAttrName(aOther.mAttrName),
mSetAttr(aOther.mSetAttr), mNeedsAttrChange(aOther.mNeedsAttrChange) {}
nsCOMPtr<Element> mBroadcaster;
nsCOMPtr<Element> mListener;
// Note if mAttrName isn't used, this is the name of the attr, otherwise
// this is the value of the attribute.
nsString mAttr;
nsCOMPtr<nsIAtom> mAttrName;
bool mSetAttr;
bool mNeedsAttrChange;
class Comparator {
public:
static bool Equals(const nsDelayedBroadcastUpdate& a, const nsDelayedBroadcastUpdate& b) {
return a.mBroadcaster == b.mBroadcaster && a.mListener == b.mListener && a.mAttrName == b.mAttrName;
}
};
};
nsTArray<nsDelayedBroadcastUpdate> mDelayedBroadcasters;
nsTArray<nsDelayedBroadcastUpdate> mDelayedAttrChangeBroadcasts;
bool mHandlingDelayedAttrChange;
bool mHandlingDelayedBroadcasters;
void MaybeBroadcast();
private:
// helpers
};
} // namespace dom
} // namespace mozilla
#endif // mozilla_dom_XULDocument_h