Make image_decoder a Leaky LazyInstance

chrome/browser/bitmap_fetcher/bitmap_fetcher.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_BITMAP_FETCHER_BITMAP_FETCHER_H_
 #define CHROME_BROWSER_BITMAP_FETCHER_BITMAP_FETCHER_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/bitmap_fetcher/bitmap_fetcher_delegate.h"
 #include "chrome/browser/image_decoder.h"
@@ skipping 41 matching lines @@
   // expected total size of the response (or -1 if not determined).
   void OnURLFetchDownloadProgress(const net::URLFetcher* source,
                                   int64 current,
                                   int64 total) override;
 
   // Methods inherited from ImageDecoder::Delegate
 
   // Called when image is decoded. |decoder| is used to identify the image in
   // case of decoding several images simultaneously.  This will not be called
   // on the UI thread.
-  void OnImageDecoded(const ImageDecoder* decoder,
-                      const SkBitmap& decoded_image) override;
+  void OnImageDecoded(const SkBitmap& decoded_image) override;
 
   // Called when decoding image failed.
-  void OnDecodeImageFailed(const ImageDecoder* decoder) override;
+  void OnDecodeImageFailed() override;
 
  private:
   // Alerts the delegate that a failure occurred.
   void ReportFailure();
 
   scoped_ptr<net::URLFetcher> url_fetcher_;
-  scoped_refptr<ImageDecoder> image_decoder_;
   const GURL url_;
   BitmapFetcherDelegate* const delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(BitmapFetcher);
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_BITMAP_FETCHER_BITMAP_FETCHER_H_