Refactor SkBitmapRegionDecoderInterface for Android

tools/SkBitmapRegionCanvas.h

Index: tools/SkBitmapRegionCanvas.h
diff --git a/tools/SkBitmapRegionCanvas.h b/tools/SkBitmapRegionCanvas.h
index f82e9fa77a941b01dee6d746d2a2fb02006ea40e..217082ac3304ef9a3a27187c9877bff0935a70ad 100644
--- a/tools/SkBitmapRegionCanvas.h
+++ b/tools/SkBitmapRegionCanvas.h
@@ -24,15 +24,9 @@ public:
      */
     SkBitmapRegionCanvas(SkCodec* decoder);
 
-    /*
-     * Three differences from the Android version:
-     *     Returns a Skia bitmap instead of an Android bitmap.
-     *     Android version attempts to reuse a recycled bitmap.
-     *     Removed the options object and used parameters for color type and
-     *     sample size.
-     */
-    SkBitmap* decodeRegion(int start_x, int start_y, int width, int height,
-                           int sampleSize, SkColorType prefColorType) override;
+    bool decodeRegion(SkBitmap* bitmap, SkBitmap::Allocator* allocator,
+                      const SkIRect& desiredSubset, int sampleSize,
+                      SkColorType colorType, bool requireUnpremul) override;
 
     bool conversionSupported(SkColorType colorType) override;