Eliminate copies of encoded image data

third_party/WebKit/Source/platform/image-decoders/gif/GIFImageReader.h

 /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* ***** BEGIN LICENSE BLOCK *****
  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
  *
  * The contents of this file are subject to the Mozilla Public License Version
  * 1.1 (the "License"); you may not use this file except in compliance with
  * the License. You may obtain a copy of the License at
  * http://www.mozilla.org/MPL/
  *
  * Software distributed under the License is distributed on an "AS IS" basis,
@@ skipping 22 matching lines @@
  * the provisions above, a recipient may use your version of this file under
  * the terms of any one of the MPL, the GPL or the LGPL.
  *
  * ***** END LICENSE BLOCK ***** */
 
 #ifndef GIFImageReader_h
 #define GIFImageReader_h
 
 // Define ourselves as the clientPtr.  Mozilla just hacked their C++ callback class into this old C decoder,
 // so we will too.
-#include "platform/SharedBuffer.h"
 #include "platform/image-decoders/FastSharedBufferReader.h"
 #include "platform/image-decoders/gif/GIFImageDecoder.h"
 #include "wtf/Allocator.h"
 #include "wtf/Noncopyable.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/Vector.h"
 
 #define MAX_DICTIONARY_ENTRY_BITS 12
 #define MAX_DICTIONARY_ENTRIES    4096 // 2^MAX_DICTIONARY_ENTRY_BITS
@@ skipping 238 matching lines @@
         , m_sentSizeToClient(false)
         , m_loopCount(cLoopCountNotSeen)
         , m_parseCompleted(false)
     {
     }
 
     ~GIFImageReader()
     {
     }
 
-    void setData(PassRefPtr<blink::SharedBuffer> data) { m_data = data; }
+    void setData(PassRefPtr<blink::SegmentReader> data) { m_data = data; }
     bool parse(blink::GIFImageDecoder::GIFParseQuery);
     bool decode(size_t frameIndex);
 
     size_t imagesCount() const
     {
         if (m_frames.isEmpty())
             return 0;
 
         // This avoids counting an empty frame when the file is truncated right after
         // GIFControlExtension but before GIFImageHeader.
@@ skipping 36 matching lines @@
     // Global (multi-image) state.
     int m_version; // Either 89 for GIF89 or 87 for GIF87.
     unsigned m_screenWidth; // Logical screen width & height.
     unsigned m_screenHeight;
     bool m_sentSizeToClient;
     GIFColorMap m_globalColorMap;
     int m_loopCount; // Netscape specific extension block to control the number of animation loops a GIF renders.
 
     Vector<OwnPtr<GIFFrameContext>> m_frames;
 
-    RefPtr<blink::SharedBuffer> m_data;
+    RefPtr<blink::SegmentReader> m_data;
     bool m_parseCompleted;
 };
 
 #endif