Add refcnting to SkClipStack on SkCanvas

include/gpu/GrClipData.h

 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrClip_DEFINED
 #define GrClip_DEFINED
 
 #include "SkClipStack.h"
 #include "GrSurface.h"
 
 struct SkIRect;
 
 /**
  * GrClipData encapsulates the information required to construct the clip
  * masks. 'fOrigin' is only non-zero when saveLayer has been called
  * with an offset bounding box. The clips in 'fClipStack' are in
  * device coordinates (i.e., they have been translated by -fOrigin w.r.t.
  * the canvas' device coordinates).
  */
 class GrClipData : SkNoncopyable {
 public:
-    const SkClipStack*  fClipStack;
-    SkIPoint            fOrigin;
+    SkAutoTUnref<const SkClipStack>  fClipStack;
+    SkIPoint                         fOrigin;
 
     GrClipData()
         : fClipStack(NULL) {
         fOrigin.setZero();
     }
 
     bool operator==(const GrClipData& other) const {
         if (fOrigin != other.fOrigin) {
             return false;
         }
@@ skipping 15 matching lines @@
         this->getConservativeBounds(surface->width(), surface->height(),
                                     devResult, isIntersectionOfRects);
     }
 
     void getConservativeBounds(int width, int height,
                                SkIRect* devResult,
                                bool* isIntersectionOfRects = NULL) const;
 };
 
 #endif