Scanline decoding for jpeg

include/codec/SkScanlineDecoder.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 SkScanlineDecoder_DEFINED
 #define SkScanlineDecoder_DEFINED
 
@@ skipping 59 matching lines @@
         return this->onReallyHasAlpha();
     }
 
 protected:
     SkScanlineDecoder(const SkImageInfo& requested)
         : fDstInfo(requested)
         , fCurrScanline(0) {}
 
     virtual bool onReallyHasAlpha() const { return false; }
 
+    const SkImageInfo& dstInfo() const { return fDstInfo; }
+
 private:
     const SkImageInfo   fDstInfo;
     int                 fCurrScanline;
 
     // Naive default version just calls onGetScanlines on temp memory.
     virtual SkImageGenerator::Result onSkipScanlines(int countLines) {
         SkAutoMalloc storage(fDstInfo.minRowBytes());
         // Note that we pass 0 to rowBytes so we continue to use the same memory.
         // Also note that while getScanlines checks that rowBytes is big enough,
         // onGetScanlines bypasses that check.
@@ skipping 16 matching lines @@
         }
     }
 
     /**
      *  This function will be called after reading/skipping all scanlines to do
      *  any necessary cleanups.
      */
     virtual void onFinish() {} // Default does nothing.
 };
 #endif // SkScanlineDecoder_DEFINED