Make image_decoder a Leaky LazyInstance

chrome/browser/media_galleries/fileapi/supported_image_type_validator.cc

 // Copyright 2013 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/media_galleries/fileapi/supported_image_type_validator.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/files/file.h"
 #include "base/location.h"
@@ skipping 43 matching lines @@
       const storage::CopyOrMoveFileValidator::ResultCallback& callback)
       : data_(data.Pass()), callback_(callback) {
     DCHECK(data_);
   }
 
   const std::string& data() {
     return *data_;
   }
 
   // ImageDecoder::Delegate methods.
-  void OnImageDecoded(const ImageDecoder* /*decoder*/,
-                      const SkBitmap& /*decoded_image*/) override {
+  void OnImageDecoded(const SkBitmap& /*decoded_image*/) override {
     callback_.Run(base::File::FILE_OK);
     delete this;
   }
 
-  void OnDecodeImageFailed(const ImageDecoder* /*decoder*/) override {
+  void OnDecodeImageFailed() override {
     callback_.Run(base::File::FILE_ERROR_SECURITY);
     delete this;
   }
 
  private:
   scoped_ptr<std::string> data_;
   storage::CopyOrMoveFileValidator::ResultCallback callback_;
 
   DISALLOW_COPY_AND_ASSIGN(ImageDecoderDelegateAdapter);
 };
@@ skipping 39 matching lines @@
 void SupportedImageTypeValidator::OnFileOpen(scoped_ptr<std::string> data) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   if (!data.get()) {
     callback_.Run(base::File::FILE_ERROR_SECURITY);
     return;
   }
 
   // |adapter| will delete itself after a completion message is received.
   ImageDecoderDelegateAdapter* adapter =
       new ImageDecoderDelegateAdapter(data.Pass(), callback_);
-  decoder_ = new ImageDecoder(adapter, adapter->data(),
-                              ImageDecoder::DEFAULT_CODEC);
-  decoder_->Start(content::BrowserThread::GetMessageLoopProxyForThread(
-      BrowserThread::IO));
+  ImageDecoder::GetInstance()->Start(
+      adapter, adapter->data(), ImageDecoder::DEFAULT_CODEC,
+      content::BrowserThread::GetMessageLoopProxyForThread(
+          BrowserThread::IO));
 }