Delete reallyHasAlpha() from SkCodec

include/codec/SkCodec.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 SkCodec_DEFINED
 #define SkCodec_DEFINED
 
@@ skipping 260 matching lines @@
     Result getPixels(const SkImageInfo& info, void* pixels, size_t rowBytes, const Options*,
                      SkPMColor ctable[], int* ctableCount);
 
     /**
      *  Simplified version of getPixels() that asserts that info is NOT kIndex8_SkColorType and
      *  uses the default Options.
      */
     Result getPixels(const SkImageInfo& info, void* pixels, size_t rowBytes);
 
     /**
-     *  Some images may initially report that they have alpha due to the format
-     *  of the encoded data, but then never use any colors which have alpha
-     *  less than 100%. This function can be called *after* decoding to
-     *  determine if such an image truly had alpha. Calling it before decoding
-     *  is undefined.
-     *  FIXME: see skbug.com/3582.
-     */
-    bool reallyHasAlpha() const {
-        return kOpaque_SkAlphaType != this->getInfo().alphaType() && this->onReallyHasAlpha();
-    }
-
-    /**
      * The remaining functions revolve around decoding scanlines.
      */
 
     /**
      *  Prepare for a scanline decode with the specified options.
      *
      *  After this call, this class will be ready to decode the first scanline.
      *
      *  This must be called in order to call getScanlines or skipScanlines.
      *
@@ skipping 177 matching lines @@
                                void* pixels, size_t rowBytes, const Options&,
                                SkPMColor ctable[], int* ctableCount,
                                int* rowsDecoded) = 0;
 
     virtual bool onGetValidSubset(SkIRect* /* desiredSubset */) const {
         // By default, subsets are not supported.
         return false;
     }
 
     /**
-     * This is only called if the image indicates that it is not opaque.
-     * By default we will assume that the image is in fact non-opaque.
-     * Subclasses may override this function if they intend to verify
-     * that the image actually has alpha.
-     */
-    virtual bool onReallyHasAlpha() const {
-        return true;
-    }
-
-    /**
      *  If the stream was previously read, attempt to rewind.
      *
      *  If the stream needed to be rewound, call onRewind.
      *  @returns true if the codec is at the right position and can be used.
      *      false if there was a failure to rewind.
      *
      *  This is called by getPixels() and start(). Subclasses may call if they
      *  need to rewind at another time.
      */
     bool SK_WARN_UNUSED_RESULT rewindIfNeeded();
@@ skipping 139 matching lines @@
      *  not affect ownership.
      *
      *  Only valid during scanline decoding.
      */
     virtual SkSampler* getSampler(bool /*createIfNecessary*/) { return nullptr; }
 
     friend class SkSampledCodec;
     friend class SkIcoCodec;
 };
 #endif // SkCodec_DEFINED