Reduce forward declarations in core/dom

Source/core/dom/Document.h

Index: Source/core/dom/Document.h
diff --git a/Source/core/dom/Document.h b/Source/core/dom/Document.h
index 6ea70357a2c097dba14769a1f089f9b0b4351f20..27b997951af95e648c68a49ef33943e326264691 100644
--- a/Source/core/dom/Document.h
+++ b/Source/core/dom/Document.h
@@ -67,25 +67,18 @@ namespace WebCore {
 class AXObjectCache;
 class Attr;
 class CDATASection;
-class CSSFontSelector;
 class CSSStyleDeclaration;
 class CSSStyleSheet;
-class CSSStyleSheetResource;
 class CanvasRenderingContext2D;
-class CharacterData;
 class Chrome;
 class Comment;
 class ContentSecurityPolicyResponseHeaders;
 class ContextFeatures;
 class CustomElementRegistrationContext;
 class DOMImplementation;
-class DOMSelection;
 class DOMWindow;
-class Database;
-class DatabaseThread;
 class DocumentFragment;
 class DocumentLifecycleNotifier;
-class DocumentLifecycleObserver;
 class DocumentLoader;
 class DocumentMarkerController;
 class DocumentParser;
@@ -101,7 +94,6 @@ class ExceptionState;
 class FastTextAutosizer;
 class FloatQuad;
 class FloatRect;
-class FontFaceSet;
 class FormController;
 class Frame;
 class FrameHost;
@@ -110,30 +102,21 @@ class HTMLAllCollection;
 class HTMLCanvasElement;
 class HTMLCollection;
 class HTMLDialogElement;
-class HTMLDocument;
 class HTMLElement;
 class HTMLFrameOwnerElement;
 class HTMLHeadElement;
-class HTMLIFrameElement;
-class HTMLImport;
 class HTMLImportLoader;
 class HTMLImportsController;
 class HTMLLinkElement;
-class HTMLMapElement;
-class HTMLNameCollection;
 class HTMLScriptElement;
 class HitTestRequest;
 class HitTestResult;
-class IntPoint;
-class JSNode;
 class LayoutPoint;
-class LayoutRect;
 class LiveNodeListBase;
 class Locale;
 class LocalFrame;
 class Location;
 class MainThreadTaskRunner;
-class MediaQueryList;
 class MediaQueryMatcher;
 class MouseEventWithHitTestResults;
 class NodeFilter;
@@ -142,14 +125,11 @@ class Page;
 class PlatformMouseEvent;
 class ProcessingInstruction;
 class Range;
-class RegisteredEventListener;
 class RenderView;
 class RequestAnimationFrameCallback;
 class ResourceFetcher;
 class SVGDocumentExtensions;
 class SVGUseElement;
-class ScriptElementData;
-class ScriptResource;
 class ScriptRunner;
 class ScriptableDocumentParser;
 class ScriptedAnimationController;
@@ -161,7 +141,6 @@ class Settings;
 class StyleEngine;
 class StyleResolver;
 class StyleSheet;
-class StyleSheetContents;
 class StyleSheetList;
 class Text;
 class TextAutosizer;
@@ -171,7 +150,6 @@ class TransformSource;
 class TreeWalker;
 class VisitedLinkState;
 class WebGLRenderingContext;
-class XMLHttpRequest;
 
 struct AnnotatedRegionValue;