Prevent image downscaling on HiDPI devices with impl-side painting.

Source/WebKit/chromium/src/LinkHighlight.h

 /*
  * Copyright (C) 2012 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:
  *
  * 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
@@ skipping 40 matching lines @@
 public:
     static PassOwnPtr<LinkHighlight> create(WebCore::Node*, WebViewImpl*);
     virtual ~LinkHighlight();
 
     WebContentLayer* contentLayer();
     WebLayer* clipLayer();
     void startHighlightAnimationIfNeeded();
     void updateGeometry();
 
     // WebContentLayerClient implementation.
-    virtual void paintContents(WebCanvas*, const WebRect& clipRect, bool canPaintLCDText, WebFloatRect& opaque) OVERRIDE;
+    virtual void paintContents(WebCanvas*, const WebRect& clipRect, bool canPaintLCDText, WebFloatRect& opaque, bool deferred = false) OVERRIDE;
 
     // WebAnimationDelegate implementation.
     virtual void notifyAnimationStarted(double time) OVERRIDE;
     virtual void notifyAnimationFinished(double time) OVERRIDE;
 
     // LinkHighlightClient inplementation.
     virtual void invalidate() OVERRIDE;
     virtual WebLayer* layer() OVERRIDE;
     virtual void clearCurrentGraphicsLayer() OVERRIDE;
 
@@ skipping 18 matching lines @@
     WebCore::GraphicsLayerChromium* m_currentGraphicsLayer;
 
     bool m_geometryNeedsUpdate;
     bool m_isAnimating;
     double m_startTime;
 };
 
 } // namespace WebKit
 
 #endif