Clean up forward declarations in Source/core

Source/core/testing/LayerRectList.h

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 22 matching lines @@
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/Vector.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 class ClientRect;
-class ClientRectList;
 class LayerRect;
 class Node;
 
 class LayerRectList final : public GarbageCollected<LayerRectList>, public ScriptWrappable {
     DEFINE_WRAPPERTYPEINFO();
 public:
     static LayerRectList* create()
     {
         return new LayerRectList;
     }
 
     unsigned length() const;
     LayerRect* item(unsigned index);
     void append(PassRefPtrWillBeRawPtr<Node> layerAssociatedNode, const String& layerName, int layerOffsetX, int layerOffsetY, PassRefPtrWillBeRawPtr<ClientRect> layerRelativeRect);
 
     void trace(Visitor*);
 
 private:
     LayerRectList();
 
     HeapVector<Member<LayerRect> > m_list;
 };
 
 } // namespace blink
 
 #endif // ClientRectList_h