Make image_decoder a Leaky LazyInstance

chrome/browser/bitmap_fetcher/bitmap_fetcher.cc

 // 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.
 
 #include "chrome/browser/bitmap_fetcher/bitmap_fetcher.h"
 
 #include "content/public/browser/browser_thread.h"
 #include "net/url_request/url_fetcher.h"
 #include "net/url_request/url_request_context_getter.h"
 #include "net/url_request/url_request_status.h"
@@ skipping 27 matching lines @@
 void BitmapFetcher::OnURLFetchComplete(const net::URLFetcher* source) {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
 
   if (source->GetStatus().status() != net::URLRequestStatus::SUCCESS) {
     ReportFailure();
     return;
   }
 
   std::string image_data;
   source->GetResponseAsString(&image_data);
-  image_decoder_ =
-      new ImageDecoder(this, image_data, ImageDecoder::DEFAULT_CODEC);
 
   // Call start to begin decoding.  The ImageDecoder will call OnImageDecoded
   // with the data when it is done.
-  scoped_refptr<base::MessageLoopProxy> task_runner =
+  ImageDecoder::GetInstance()->Start(
+      this,
+      image_data,
+      ImageDecoder::DEFAULT_CODEC,
       content::BrowserThread::GetMessageLoopProxyForThread(
-          content::BrowserThread::UI);
-  image_decoder_->Start(task_runner);
+          content::BrowserThread::UI));
 }
 
 void BitmapFetcher::OnURLFetchDownloadProgress(const net::URLFetcher* source,
                                                int64 current,
                                                int64 total) {
   // Do nothing here.
 }
 
 // Methods inherited from ImageDecoder::Delegate.
 
-void BitmapFetcher::OnImageDecoded(const ImageDecoder* decoder,
-                                   const SkBitmap& decoded_image) {
+void BitmapFetcher::OnImageDecoded(const SkBitmap& decoded_image) {
   // Report success.
   delegate_->OnFetchComplete(url_, &decoded_image);
 }
 
-void BitmapFetcher::OnDecodeImageFailed(const ImageDecoder* decoder) {
+void BitmapFetcher::OnDecodeImageFailed() {
   ReportFailure();
 }
 
 void BitmapFetcher::ReportFailure() {
   delegate_->OnFetchComplete(url_, NULL);
 }
 
 }  // namespace chrome