Reduce forward declarations in core/dom

Source/core/dom/Position.h

 /*
  * Copyright (C) 2004, 2006, 2008 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 22 matching lines @@
 #include "wtf/Assertions.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefPtr.h"
 
 namespace WebCore {
 
 class CSSComputedStyleDeclaration;
 class Element;
 class InlineBox;
 class Node;
-class Range;
 class RenderObject;
 class Text;
 
 enum PositionMoveType {
     CodePoint,       // Move by a single code point.
     Character,       // Move to the next Unicode character break.
     BackwardDeletion // Subject to platform conventions.
 };
 
 class Position {
@@ skipping 286 matching lines @@
 
 } // namespace WebCore
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showTree(const WebCore::Position&);
 void showTree(const WebCore::Position*);
 #endif
 
 #endif // Position_h