Add reallyHasAlpha() to SkAndroidCodec

src/codec/SkSampledCodec.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 SkSampledCodec_DEFINED
 #define SkSampledCodec_DEFINED
 
 #include "SkAndroidCodec.h"
 #include "SkCodec.h"
 
 /**
  *  This class implements the functionality of SkAndroidCodec.  Scaling will
  *  be provided by sampling if it cannot be provided by fCodec.
  */
 class SkSampledCodec : public SkAndroidCodec {
 public:
 
     explicit SkSampledCodec(SkCodec*);
 
     virtual ~SkSampledCodec() {}
 
 protected:
 
-    SkEncodedFormat onGetEncodedFormat() const override { return fCodec->getEncodedFormat(); };
-
     SkISize onGetSampledDimensions(int sampleSize) const override;
 
     bool onGetSupportedSubset(SkIRect* desiredSubset) const override { return true; }
 
     SkCodec::Result onGetAndroidPixels(const SkImageInfo& info, void* pixels, size_t rowBytes,
             const AndroidOptions& options) override;
 
 private:
     /**
      *  Find the best way to account for native scaling.
@@ skipping 12 matching lines @@
     /**
      *  This fulfills the same contract as onGetAndroidPixels().
      *
      *  We call this function from onGetAndroidPixels() if we have determined
      *  that fCodec does not support the requested scale, and we need to
      *  provide the scale by sampling.
      */
     SkCodec::Result sampledDecode(const SkImageInfo& info, void* pixels, size_t rowBytes,
             const AndroidOptions& options);
 
-    SkAutoTDelete<SkCodec> fCodec;
-
     typedef SkAndroidCodec INHERITED;
 };
 #endif // SkSampledCodec_DEFINED