Make 2D canvas smarter about chosing whether or not to use GPU acceleration

third_party/WebKit/Source/core/editing/Editor.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  *
  * 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.
  * 2. Redistributions in binary form must reproduce the above copyright
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 }
 
 static PassRefPtr<Image> imageFromNode(const Node& node)
 {
     node.document().updateLayoutIgnorePendingStylesheets();
     LayoutObject* layoutObject = node.layoutObject();
     if (!layoutObject)
         return nullptr;
 
     if (layoutObject->isCanvas())
-        return toHTMLCanvasElement(node).copiedImage(FrontBuffer);
+        return toHTMLCanvasElement(node).copiedImage(FrontBuffer, PreferNoAcceleration);
 
     if (layoutObject->isImage()) {
         LayoutImage* layoutImage = toLayoutImage(layoutObject);
         if (!layoutImage)
             return nullptr;
 
         ImageResource* cachedImage = layoutImage->cachedImage();
         if (!cachedImage || cachedImage->errorOccurred())
             return nullptr;
         return cachedImage->imageForLayoutObject(layoutImage);
@@ skipping 862 matching lines @@
 }
 
 DEFINE_TRACE(Editor)
 {
     visitor->trace(m_frame);
     visitor->trace(m_lastEditCommand);
     visitor->trace(m_mark);
 }
 
 } // namespace blink