Option for SkCodec to treat dst as all zeroes.

src/codec/SkCodec_libbmp.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.
  */
 
 #include "SkCodec.h"
 #include "SkImageInfo.h"
 #include "SkMaskSwizzler.h"
@@ skipping 38 matching lines @@
     static SkCodec* NewFromStream(SkStream*);
 
 protected:
 
     /*
      *
      * Initiates the bitmap decode
      *
      */
     virtual Result onGetPixels(const SkImageInfo& dstInfo, void* dst,
-                               size_t dstRowBytes, SkPMColor*,
+                               size_t dstRowBytes, const Options&, SkPMColor*,
                                int*) SK_OVERRIDE;
 
 private:
 
     /*
      *
      * Used to define the input format of the bitmap
      *
      */
     enum BitmapInputFormat {
@@ skipping 63 matching lines @@
     // Fields
     const uint16_t                      fBitsPerPixel;
     const BitmapInputFormat             fInputFormat;
     SkAutoTDelete<SkMasks>              fMasks;          // owned
     const SkAutoTDeleteArray<SkPMColor> fColorTable;     // owned, unpremul
     const RowOrder                      fRowOrder;
     const uint32_t                      fRemainingBytes;
 
     typedef SkCodec INHERITED;
 };