Remove unused includes from core/{editing,fileapi,history,html}

Source/core/html/canvas/WebGLRenderbuffer.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 11 matching lines @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
  */
 
 #ifndef WebGLRenderbuffer_h
 #define WebGLRenderbuffer_h
 
 #include "bindings/v8/ScriptWrappable.h"
 #include "core/html/canvas/WebGLSharedObject.h"
 #include "wtf/PassRefPtr.h"
-#include "wtf/RefCounted.h"
 
 namespace WebCore {
 
 class WebGLRenderbuffer : public WebGLSharedObject, public ScriptWrappable {
 public:
     virtual ~WebGLRenderbuffer();
 
     static PassRefPtr<WebGLRenderbuffer> create(WebGLRenderingContext*);
 
     void setInternalFormat(GC3Denum internalformat)
@@ skipping 35 matching lines @@
     GC3Dsizei m_width, m_height;
 
     bool m_hasEverBeenBound;
 
     RefPtr<WebGLRenderbuffer> m_emulatedStencilBuffer;
 };
 
 } // namespace WebCore
 
 #endif // WebGLRenderbuffer_h