Use refs for GraphicsContext

third_party/WebKit/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
 
 #include "wtf/Allocator.h"
 
 namespace blink {
 
 class GraphicsContext;
 struct PaintInfo;
 class LayoutPoint;
 class LayoutRect;
 class LayoutImage;
 
 class ImagePainter {
     STACK_ALLOCATED();
 public:
     ImagePainter(const LayoutImage& layoutImage) : m_layoutImage(layoutImage) { }
 
     void paint(const PaintInfo&, const LayoutPoint& paintOffset);
     void paintReplaced(const PaintInfo&, const LayoutPoint& paintOffset);
-    void paintIntoRect(GraphicsContext*, const LayoutRect&);
+    void paintIntoRect(GraphicsContext&, const LayoutRect&);
 
 private:
     void paintAreaElementFocusRing(const PaintInfo&, const LayoutPoint& paintOffset);
 
     const LayoutImage& m_layoutImage;
 };
 
 } // namespace blink
 
 #endif // ImagePainter_h