Fix display list canvas not rendering correctly on high dpi displays

Source/platform/graphics/ImageBufferSurface.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 15 matching lines @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef ImageBufferSurface_h
 #define ImageBufferSurface_h
 
 #include "platform/PlatformExport.h"
 #include "platform/geometry/IntSize.h"
+#include "platform/graphics/GraphicsTypes.h"
 #include "platform/graphics/GraphicsTypes3D.h"
 #include "wtf/FastAllocBase.h"
 #include "wtf/Noncopyable.h"
 #include "wtf/PassRefPtr.h"
 
 class SkBitmap;
 class SkCanvas;
 class SkImage;
 class SkPicture;
 
 namespace blink {
 
 class ImageBuffer;
 class WebLayer;
 class FloatRect;
+class GraphicsContext;
 
 enum OpacityMode {
     NonOpaque,
     Opaque,
 };
 
 class PLATFORM_EXPORT ImageBufferSurface {
     WTF_MAKE_NONCOPYABLE(ImageBufferSurface); WTF_MAKE_FAST_ALLOCATED;
 public:
     virtual ~ImageBufferSurface();
@@ skipping 12 matching lines @@
     virtual const SkBitmap& cachedBitmap() const;
     virtual void invalidateCachedBitmap() { }
     virtual void updateCachedBitmapIfNeeded() { }
     virtual void setIsHidden(bool) { }
     virtual void setImageBuffer(ImageBuffer*) { }
     virtual PassRefPtr<SkPicture> getPicture();
     virtual void didClearCanvas() { }
     virtual void finalizeFrame(const FloatRect &dirtyRect) { }
     virtual void willDrawVideo() { }
     virtual PassRefPtr<SkImage> newImageSnapshot() const;
+    virtual void draw(GraphicsContext*, const FloatRect& destRect, const FloatRect& srcRect, CompositeOperator, WebBlendMode, bool needsCopy);
 
     OpacityMode opacityMode() const { return m_opacityMode; }
     const IntSize& size() const { return m_size; }
     void notifyIsValidChanged(bool isValid) const;
 
 protected:
     ImageBufferSurface(const IntSize&, OpacityMode);
     void clear();
 
 private:
     OpacityMode m_opacityMode;
     IntSize m_size;
 };
 
 } // namespace blink
 
 #endif