Don't anti-alias backgrounds of images.

Source/core/paint/ImagePainter.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ImagePainter_h
 #define ImagePainter_h
 
 namespace blink {
 
 class GraphicsContext;
 struct PaintInfo;
 class LayoutPoint;
 class LayoutRect;
 class RenderImage;
 
 class ImagePainter {
 public:
     ImagePainter(RenderImage& renderImage) : m_renderImage(renderImage) { }
 
-    void paint(PaintInfo&, const LayoutPoint&);
-    void paintReplaced(PaintInfo&, const LayoutPoint&);
-    void paintIntoRect(GraphicsContext*, const LayoutRect&);
+    void paint(PaintInfo&, const LayoutPoint& paintOffset);
+    void paintReplaced(PaintInfo&, const LayoutPoint& paintOffset);
+    void paintIntoRect(GraphicsContext*, const LayoutRect& paintOffset);
+    void paintBoxDecorationBackground(PaintInfo&, const LayoutPoint& paintOffset);
 
 private:
     void paintAreaElementFocusRing(PaintInfo&);
 
     RenderImage& m_renderImage;
 };
 
 } // namespace blink
 
 #endif // ImagePainter_h