SkBitmapRegionDecoder clean-up

tools/SkBitmapRegionDecoderInterface.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 SkBitmapRegionDecoder_DEFINED
 #define SkBitmapRegionDecoder_DEFINED
 
@@ skipping 38 matching lines @@
      *                   New implementations should return NULL if they do not support
      *                   decoding to this color type.
      *                   The old kOriginal_Strategy will decode to a default color type
      *                   if this color type is unsupported.
      * @return           Pointer to a bitmap of the decoded region on success, NULL on
      *                   failure.
      */
     virtual SkBitmap* decodeRegion(int start_x, int start_y, int width,
                                    int height, int sampleSize,
                                    SkColorType colorType) = 0;
+    /*
+     * @param  Requested destination color type
+     * @return true if we support the requested color type and false otherwise
+     */
+    virtual bool conversionSupported(SkColorType colorType) = 0;
 
     int width() const { return fWidth; }
     int height() const { return fHeight; }
 
     virtual ~SkBitmapRegionDecoderInterface() {}
 
 protected:
 
     SkBitmapRegionDecoderInterface(int width, int height)
         : fWidth(width)
         , fHeight(height)
     {}
 
 private:
     const int fWidth;
     const int fHeight;
 };
 
 #endif