Use SkImageCacherator in SkImages

src/gpu/SkGrPriv.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkGrPriv_DEFINED
 #define SkGrPriv_DEFINED
 
 #include "GrTypes.h"
 #include "SkPoint.h"
 
 class GrCaps;
 class GrUniqueKey;
 
 /**
  *  Our key includes the offset, width, and height so that bitmaps created by extractSubset()
  *  are unique.
  *
  *  The imageID is in the shared namespace (see SkNextID::ImageID()
  *      - SkBitmap/SkPixelRef
  *      - SkImage
  *      - SkImageGenerator
  *
  *  Note: width/height must fit in 16bits for this impl.
  */
-void GrMakeKeyFromImageID(GrUniqueKey* key, uint32_t imageID,
-                          U16CPU width, U16CPU height, SkIPoint origin,
+void GrMakeKeyFromImageID(GrUniqueKey* key, uint32_t imageID, const SkIRect& imageBounds,
                           const GrCaps&, SkImageUsageType);
 
 #endif