Clean up forward declarations in Source/core/html

Source/core/html/canvas/CanvasRenderingContext.h

 /*
  * Copyright (C) 2009 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 20 matching lines @@
 #include "wtf/HashSet.h"
 #include "wtf/Noncopyable.h"
 #include "wtf/text/StringHash.h"
 
 namespace blink { class WebLayer; }
 
 namespace blink {
 
 class CanvasImageSource;
 class HTMLCanvasElement;
-class KURL;
-class WebGLObject;
 
 class CanvasRenderingContext : public NoBaseWillBeGarbageCollectedFinalized<CanvasRenderingContext> {
     WTF_MAKE_NONCOPYABLE(CanvasRenderingContext);
     WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED;
 public:
     virtual ~CanvasRenderingContext() { }
 
 #if !ENABLE(OILPAN)
     void ref() { m_canvas->ref(); }
     void deref() { m_canvas->deref(); }
@@ skipping 20 matching lines @@
 
 private:
     RawPtrWillBeMember<HTMLCanvasElement> m_canvas;
     HashSet<String> m_cleanURLs;
     HashSet<String> m_dirtyURLs;
 };
 
 } // namespace blink
 
 #endif