Use refs for GraphicsContext

third_party/WebKit/Source/platform/mac/LocalCurrentGraphicsContext.h

 /*
  * Copyright (C) 2006 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 17 matching lines @@
 
 namespace blink {
 
 class GraphicsContext;
 
 // This class automatically saves and restores the current NSGraphicsContext for
 // functions which call out into AppKit and rely on the currentContext being set
 class PLATFORM_EXPORT LocalCurrentGraphicsContext {
     WTF_MAKE_NONCOPYABLE(LocalCurrentGraphicsContext);
 public:
-    LocalCurrentGraphicsContext(GraphicsContext*, const IntRect& dirtyRect);
+    LocalCurrentGraphicsContext(GraphicsContext&, const IntRect& dirtyRect);
     // Allows specifying an interest rect to which we clip if slimming paint is enabled and performance would benefit.
-    LocalCurrentGraphicsContext(GraphicsContext*, const IntRect* interestRect, const IntRect& dirtyRect);
+    LocalCurrentGraphicsContext(GraphicsContext&, const IntRect* interestRect, const IntRect& dirtyRect);
     LocalCurrentGraphicsContext(SkCanvas*, float deviceScaleFactor, const IntRect* interestRect, const IntRect& dirtyRect);
     ~LocalCurrentGraphicsContext();
     CGContextRef cgContext();
 private:
 
     SkCanvas* m_savedCanvas;
     NSGraphicsContext* m_savedNSGraphicsContext;
     bool m_didSetGraphicsContext;
     IntRect m_inflatedDirtyRect;
     gfx::SkiaBitLocker m_skiaBitLocker;
 };
 
 }