Make SkImage_Gpu share it's pixelref with the surface to prevent premature return to scratch pool.

include/core/SkImage.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkImage_DEFINED
 #define SkImage_DEFINED
 
@@ skipping 47 matching lines @@
     struct Info {
         int         fWidth;
         int         fHeight;
         ColorType   fColorType;
         AlphaType   fAlphaType;
     };
 
     static SkImage* NewRasterCopy(const Info&, const void* pixels, size_t rowBytes);
     static SkImage* NewRasterData(const Info&, SkData* pixels, size_t rowBytes);
     static SkImage* NewEncodedData(SkData*);
-    static SkImage* NewTexture(GrTexture*);
+
+    /**
+     * GrTexture is a more logical parameter for this factory, but its 
+     * interactions with scratch cache still has issues, so for now we take
+     * SkBitmap instead. This will be changed in the future. skbug.com/1449
+     */
+    static SkImage* NewTexture(const SkBitmap&);
 
     int width() const { return fWidth; }
     int height() const { return fHeight; }
     uint32_t uniqueID() const { return fUniqueID; }
 
     /**
      * Return the GrTexture that stores the image pixels. Calling getTexture
      * does not affect the reference count of the GrTexture object.
      * Will return NULL if the image does not use a texture.
      */
@@ skipping 37 matching lines @@
     const int       fWidth;
     const int       fHeight;
     const uint32_t  fUniqueID;
 
     static uint32_t NextUniqueID();
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif