Fill incomplete images in SkCodec parent class

src/codec/SkBmpCodec.h

Index: src/codec/SkBmpCodec.h
diff --git a/src/codec/SkBmpCodec.h b/src/codec/SkBmpCodec.h
index 4b2cd2a268b7c523a233853c46f9d03993d21333..21f4e233aaca974c6482c851f624c69b0cb1d761 100644
--- a/src/codec/SkBmpCodec.h
+++ b/src/codec/SkBmpCodec.h
@@ -96,7 +96,7 @@ protected:
      * we start filling from where we left off, but for kBottomUp we start
      * filling at the top of the image.
      */
-    void* getDstStartRow(void* dst, size_t dstRowBytes, int32_t y) const;
+    void* onGetFillDst(void* dst, size_t dstRowBytes, uint32_t decodedScanlines) const override;
 
     /*
      * Compute the number of colors in the color table
@@ -149,8 +149,9 @@ private:
      *                    number of rows to decode at this time.
      * @param dst         Memory location to store output pixels
      * @param dstRowBytes Bytes in a row of the destination
+     * @return            Number of rows successfully decoded
      */
-    virtual Result decodeRows(const SkImageInfo& dstInfo, void* dst, size_t dstRowBytes,
+    virtual uint32_t decodeRows(const SkImageInfo& dstInfo, void* dst, size_t dstRowBytes,
             const Options& opts) = 0;
 
     const uint16_t                           fBitsPerPixel;