Establish mojo service between Canvas (blink) and SurfaceManager (browser)

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 1148 matching lines @@
     return std::make_pair(nullptr, String());
 }
 
 String HTMLCanvasElement::getIdFromControl(const Element* element)
 {
     if (m_context)
         return m_context->getIdFromControl(element);
     return String();
 }
 
-void HTMLCanvasElement::createSurfaceLayerBridge()
+CanvasSurfaceLayerBridge* HTMLCanvasElement::getSurfaceLayerBridge()
 {
-    m_surfaceLayerBridge = adoptPtr(new CanvasSurfaceLayerBridge());
+    if (!m_surfaceLayerBridge.get())
+        m_surfaceLayerBridge = adoptPtr(new CanvasSurfaceLayerBridge());
+    return m_surfaceLayerBridge.get();
 }
 
 } // namespace blink