Remove opaque alpha channel special case

third_party/WebKit/Source/platform/image-decoders/ImageDecoder.h

Index: third_party/WebKit/Source/platform/image-decoders/ImageDecoder.h
diff --git a/third_party/WebKit/Source/platform/image-decoders/ImageDecoder.h b/third_party/WebKit/Source/platform/image-decoders/ImageDecoder.h
index 4cf7f23eaeb0cae45c9583eb7863b5741b8e0a9b..4cee6d1df330953556d5779e9bb1d1153c7618a0 100644
--- a/third_party/WebKit/Source/platform/image-decoders/ImageDecoder.h
+++ b/third_party/WebKit/Source/platform/image-decoders/ImageDecoder.h
@@ -342,18 +342,6 @@ class PLATFORM_EXPORT ImageDecoder {
   //         false otherwise.
   bool postDecodeProcessing(size_t);
 
-  // The GIF and PNG decoders set the default alpha setting of the ImageFrame to
-  // true. When the frame rect does not contain any (semi-) transparent pixels,
-  // this may need to be changed to false. This depends on whether the required
-  // previous frame adds transparency to the image, outside of the frame rect.
-  // This methods corrects the alpha setting of the frame buffer to false when
-  // the whole frame is opaque.
-  //
-  // This method should be called by the GIF and PNG decoder when the pixels in
-  // the frame rect do *not* contain any transparent pixels. Before calling
-  // this method, the caller must verify that the frame exists.
-  void correctAlphaWhenFrameBufferSawNoAlpha(size_t);
-
   RefPtr<SegmentReader> m_data;  // The encoded data.
   Vector<ImageFrame, 1> m_frameBufferCache;
   const bool m_premultiplyAlpha;