Make OffscreenCanvas a member of CanvasImageSource

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 237 matching lines @@
     return m_context.get();
 }
 
 bool HTMLCanvasElement::shouldBeDirectComposited() const
 {
     return (m_context && m_context->isAccelerated()) || (hasImageBuffer() && buffer()->isExpensiveToPaint()) || (!!m_surfaceLayerBridge);
 }
 
 bool HTMLCanvasElement::isPaintable() const
 {
-    if (!m_context)
-        return ImageBuffer::canCreateImageBuffer(size());
-    if (m_context->getContextType() == CanvasRenderingContext::ContextImageBitmap)
-        return (renderingContext()->getImage().get());
-    return buffer();
+    return (m_context && m_context->isPaintable()) || ImageBuffer::canCreateImageBuffer(size());
 }
 
 void HTMLCanvasElement::didDraw(const FloatRect& rect)
 {
     if (rect.isEmpty())
         return;
     m_imageBufferIsClear = false;
     clearCopiedImage();
     if (layoutObject())
         layoutObject()->setMayNeedPaintInvalidation();
@@ skipping 844 matching lines @@
     if (!m_context) {
         *status = NormalSourceImageStatus;
         return createTransparentImage(size());
     }
 
     if (m_context->is3d()) {
         m_context->paintRenderingResultsToCanvas(BackBuffer);
     }
 
     RefPtr<SkImage> skImage;
-    RefPtr<blink::Image> image = renderingContext()->getImage();
+    RefPtr<blink::Image> image = renderingContext()->getImage(reason);
 
     if (image)
         skImage = image->imageForCurrentFrame();
-    else
-        skImage = hasImageBuffer() ? buffer()->newSkImageSnapshot(hint, reason) : createTransparentImage(size())->imageForCurrentFrame();
 
     if (skImage) {
         *status = NormalSourceImageStatus;
         return StaticBitmapImage::create(skImage.release());
     }
 
     *status = InvalidSourceImageStatus;
     return nullptr;
 }
 
@@ skipping 102 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