Revert of Scanline decoding for gifs

src/codec/SkScanlineDecoder.cpp

 /*
  * 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 "SkScanlineDecoder.h"
 #include "SkBmpCodec.h"
-#include "SkCodec_libgif.h"
 #include "SkCodec_libpng.h"
 #include "SkCodec_wbmp.h"
 #include "SkCodecPriv.h"
 #ifndef SK_BUILD_FOR_ANDROID_FRAMEWORK
 #include "SkJpegCodec.h"
 #endif
 
 struct DecoderProc {
     bool (*IsFormat)(SkStream*);
     SkScanlineDecoder* (*NewFromStream)(SkStream*);
 };
 
 static const DecoderProc gDecoderProcs[] = {
     { SkPngCodec::IsPng, SkPngCodec::NewSDFromStream },
 #ifndef SK_BUILD_FOR_ANDROID_FRAMEWORK
     { SkJpegCodec::IsJpeg, SkJpegCodec::NewSDFromStream },
 #endif
-    { SkGifCodec::IsGif, SkGifCodec::NewSDFromStream },
     { SkBmpCodec::IsBmp, SkBmpCodec::NewSDFromStream },
     { SkWbmpCodec::IsWbmp, SkWbmpCodec::NewSDFromStream },
 };
 
 SkScanlineDecoder* SkScanlineDecoder::NewFromStream(SkStream* stream) {
     if (!stream) {
         return nullptr;
     }
 
     SkAutoTDelete<SkStream> streamDeleter(stream);
@@ skipping 60 matching lines @@
     fCurrScanline = 0;
     fDstInfo = dstInfo;
     fOptions = *options;
     return SkCodec::kSuccess;
 }
 
 SkCodec::Result SkScanlineDecoder::start(const SkImageInfo& dstInfo) {
     return this->start(dstInfo, nullptr, nullptr, nullptr);
 }