Make 2D canvas disable gpu acceleration when getImageData is called

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

Index: third_party/WebKit/Source/platform/graphics/Canvas2DImageBufferSurface.h
diff --git a/third_party/WebKit/Source/platform/graphics/Canvas2DImageBufferSurface.h b/third_party/WebKit/Source/platform/graphics/Canvas2DImageBufferSurface.h
index 813a9484c3af7d43b2078e641c957919d8f2674e..dfffd7eea448618230d83221f364be35cb336182 100644
--- a/third_party/WebKit/Source/platform/graphics/Canvas2DImageBufferSurface.h
+++ b/third_party/WebKit/Source/platform/graphics/Canvas2DImageBufferSurface.h
@@ -43,6 +43,18 @@ public:
         : ImageBufferSurface(size, opacityMode)
         , m_layerBridge(Canvas2DLayerBridge::create(size, msaaSampleCount, opacityMode, accelerationMode))
     {
+        init();
+    }
+
+    Canvas2DImageBufferSurface(PassRefPtr<Canvas2DLayerBridge> bridge, const IntSize& size, OpacityMode opacityMode)
+        : ImageBufferSurface(size, opacityMode)

[xlai (Olivia), 2016/06/23 19:55:02]

I think you could take away the opacityMode para from the constructor and just
deduce it from bridge->opacityMode. This is to avoid potential use of
constructor with two diffferent opacity mode for ImageBufferSurface and bridge.

[Justin Novosad, 2016/06/23 21:02:09]

Done.

+        , m_layerBridge(std::move(bridge))
+    {
+        init();
+    }
+
+    void init()
+    {
         clear();
         if (isValid())
             m_layerBridge->flush();