Ensure ImageBuffer is never used with ImageBitmapRenderingContext

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 965 matching lines @@
 {
     if (!hasImageBuffer())
         return nullptr;
 
     return m_imageBuffer->canvas();
 }
 
 ImageBuffer* HTMLCanvasElement::buffer() const
 {
     DCHECK(m_context);
+    DCHECK(m_context->getContextType() != CanvasRenderingContext::ContextImageBitmap);
     if (!hasImageBuffer() && !m_didFailToCreateImageBuffer)
         const_cast<HTMLCanvasElement*>(this)->createImageBuffer();
     return m_imageBuffer.get();
 }
 
 void HTMLCanvasElement::createImageBufferUsingSurfaceForTesting(std::unique_ptr<ImageBufferSurface> surface)
 {
     discardImageBuffer();
     setWidth(surface->size().width());
     setHeight(surface->size().height());
@@ skipping 220 matching lines @@
 
 bool HTMLCanvasElement::createSurfaceLayer()
 {
     DCHECK(!m_surfaceLayerBridge);
     std::unique_ptr<CanvasSurfaceLayerBridgeClient> bridgeClient = wrapUnique(new CanvasSurfaceLayerBridgeClientImpl());
     m_surfaceLayerBridge = wrapUnique(new CanvasSurfaceLayerBridge(std::move(bridgeClient)));
     return m_surfaceLayerBridge->createSurfaceLayer(this->width(), this->height());
 }
 
 } // namespace blink