[Oilpan] Prepare full definition of classes before using Member

third_party/WebKit/Source/core/html/HTMLCanvasElement.cpp

 /*
  * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. 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.
@@ skipping 768 matching lines @@
 }
 
 SkCanvas* HTMLCanvasElement::existingDrawingCanvas() const
 {
     if (!hasImageBuffer())
         return nullptr;
 
     return m_imageBuffer->canvas();
 }
 
+CanvasRenderingContext* HTMLCanvasElement::renderingContext() const
+{
+    return m_context.get();
+}
+
 ImageBuffer* HTMLCanvasElement::buffer() const
 {
     ASSERT(m_context);
     if (!hasImageBuffer() && !m_didFailToCreateImageBuffer)
         const_cast<HTMLCanvasElement*>(this)->createImageBuffer();
     return m_imageBuffer.get();
 }
 
 void HTMLCanvasElement::createImageBufferUsingSurfaceForTesting(PassOwnPtr<ImageBufferSurface> surface)
 {
@@ skipping 121 matching lines @@
 {
     return FloatSize(width(), height());
 }
 
 bool HTMLCanvasElement::isOpaque() const
 {
     return m_context && !m_context->hasAlpha();
 }
 
 } // blink