Skia side RGB to YUV gpu conversion

include/core/SkImageGenerator.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkImageGenerator_DEFINED
 #define SkImageGenerator_DEFINED
 
@@ skipping 98 matching lines @@
      */
     bool getPixels(const SkImageInfo& info, void* pixels, size_t rowBytes,
                    SkPMColor ctable[], int* ctableCount);
 
     /**
      *  Simplified version of getPixels() that asserts that info is NOT kIndex8_SkColorType.
      */
     bool getPixels(const SkImageInfo& info, void* pixels, size_t rowBytes);
 #endif
 
+    /**
+     *  If any planes or rowBytes is NULL, this imagegenerator should output the sizes and return
+     *  true if it can efficiently return YUV planar data. If it cannot, it should return false.
+     *
+     *  If all planes and rowBytes are not NULL, then it should copy the associated Y,U,V data into
+     *  those planes of memory supplied by the caller. It should validate that the sizes match what
+     *  it expected. If the sizes do not match, it should return false.
+     */
+    bool getYUV8Planes(SkISize sizes[3], void* planes[3], size_t rowBytes[3]);
+
 protected:
     virtual SkData* onRefEncodedData();
     virtual bool onGetInfo(SkImageInfo* info);
     virtual bool onGetPixels(const SkImageInfo& info,
                              void* pixels, size_t rowBytes,
                              SkPMColor ctable[], int* ctableCount);
+    virtual bool onGetYUV8Planes(SkISize sizes[3], void* planes[3], size_t rowBytes[3]);
 };
 
 #endif  // SkImageGenerator_DEFINED