Make image_decoder a Leaky LazyInstance

chrome/browser/chromeos/login/users/avatar/user_image_loader.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_CHROMEOS_LOGIN_USERS_AVATAR_USER_IMAGE_LOADER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_AVATAR_USER_IMAGE_LOADER_H_
 
-#include <map>
+#include <queue>
 #include <string>
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "chrome/browser/image_decoder.h"
 
 class SkBitmap;
 
 namespace base {
@@ skipping 41 matching lines @@
     ImageInfo(const std::string& file_path,
               int pixels_per_side,
               const LoadedCallback& loaded_cb);
     ~ImageInfo();
 
     const std::string file_path;
     const int pixels_per_side;
     const LoadedCallback loaded_cb;
   };
 
-  typedef std::map<const ImageDecoder*, ImageInfo> ImageInfoMap;
+  // Contains attributes retain for after the image is decoded.
+  struct ImageData {
+    ImageData(const ImageInfo& image_info, const std::string& data);
+    ~ImageData();
+
+    const ImageInfo image_info;
+    std::vector<unsigned char> data;
+  };
+
+  typedef std::queue<ImageData> ImageDataQueue;
 
   ~UserImageLoader() override;
 
   // Reads the image from |image_info.file_path| and starts the decoding
   // process. This method may only be invoked via the |background_task_runner_|.
   void ReadAndDecodeImage(const ImageInfo& image_info);
 
   // Decodes the image |data|. This method may only be invoked via the
   // |background_task_runner_|.
   void DecodeImage(const scoped_ptr<std::string> data,
                    const ImageInfo& image_info);
 
   // ImageDecoder::Delegate implementation. These callbacks will only be invoked
   // via the |background_task_runner_|.
-  void OnImageDecoded(const ImageDecoder* decoder,
-                      const SkBitmap& decoded_image) override;
-  void OnDecodeImageFailed(const ImageDecoder* decoder) override;
+  void OnImageDecoded(const SkBitmap& decoded_image) override;
+  void OnDecodeImageFailed() override;
 
   // The foreground task runner on which |this| is instantiated, Start() is
   // called and LoadedCallbacks are invoked.
   scoped_refptr<base::SequencedTaskRunner> foreground_task_runner_;
 
   // The background task runner on which file I/O, image decoding and resizing
   // are done.
   scoped_refptr<base::SequencedTaskRunner> background_task_runner_;
 
   // Specify how the file should be decoded in the utility process.
   const ImageDecoder::ImageCodec image_codec_;
 
   // Holds information about the images currently being decoded. Accessed via
   // |background_task_runner_| only.
-  ImageInfoMap image_info_map_;
+  ImageDataQueue image_data_queue_;
 
   DISALLOW_COPY_AND_ASSIGN(UserImageLoader);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_AVATAR_USER_IMAGE_LOADER_H_