Reland: Make 2D canvas disable gpu acceleration when getImageData is called

third_party/WebKit/Source/platform/graphics/Canvas2DImageBufferSurface.h

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 25 matching lines @@
 
 namespace blink {
 
 // This shim necessary because ImageBufferSurfaces are not allowed to be RefCounted
 class Canvas2DImageBufferSurface final : public ImageBufferSurface {
 public:
     Canvas2DImageBufferSurface(const IntSize& size, int msaaSampleCount, OpacityMode opacityMode, Canvas2DLayerBridge::AccelerationMode accelerationMode)
         : ImageBufferSurface(size, opacityMode)
         , m_layerBridge(Canvas2DLayerBridge::create(size, msaaSampleCount, opacityMode, accelerationMode))
     {
+        init();
+    }
+
+    Canvas2DImageBufferSurface(PassRefPtr<Canvas2DLayerBridge> bridge, const IntSize& size)
+        : ImageBufferSurface(size, bridge->opacityMode())
+        , m_layerBridge(std::move(bridge))
+    {
+        init();
+    }
+
+    void init()
+    {
         clear();
         if (isValid())
             m_layerBridge->flush();
     }
 
     ~Canvas2DImageBufferSurface() override
     {
         if (m_layerBridge)
             m_layerBridge->beginDestruction();
     }
@@ skipping 17 matching lines @@
     bool writePixels(const SkImageInfo& origInfo, const void* pixels, size_t rowBytes, int x, int y) override { return m_layerBridge->writePixels(origInfo, pixels, rowBytes, x, y); }
 
     PassRefPtr<SkImage> newImageSnapshot(AccelerationHint hint, SnapshotReason reason) override { return m_layerBridge->newImageSnapshot(hint, reason); }
 private:
     RefPtr<Canvas2DLayerBridge> m_layerBridge;
 };
 
 } // namespace blink
 
 #endif