Moving GraphicsContext and dependencies from core to platform.

Source/core/html/canvas/WebGLRenderingContext.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 12 matching lines @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef WebGLRenderingContext_h
 #define WebGLRenderingContext_h
 
 #include "core/dom/ActiveDOMObject.h"
 #include "core/html/canvas/CanvasRenderingContext.h"
 #include "core/html/canvas/WebGLGetInfo.h"
 #include "core/page/Page.h"
-#include "core/platform/graphics/GraphicsContext3D.h"
-#include "core/platform/graphics/ImageBuffer.h"
 #include "platform/Timer.h"
+#include "platform/graphics/GraphicsContext3D.h"
+#include "platform/graphics/ImageBuffer.h"
 
 #include "wtf/Float32Array.h"
 #include "wtf/Int32Array.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink { class WebLayer; }
 
 namespace WebCore {
 
@@ skipping 878 matching lines @@
     // If the vector is empty, return the maximum allowed active context number.
     static size_t oldestContextIndex();
     static IntSize oldestContextSize();
 };
 
 DEFINE_TYPE_CASTS(WebGLRenderingContext, CanvasRenderingContext, context, context->is3d(), context.is3d());
 
 } // namespace WebCore
 
 #endif