Refactor extension app icon.

chrome/browser/extensions/extension_app_icon_loader.h

 // Copyright 2016 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_EXTENSIONS_EXTENSION_APP_ICON_LOADER_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_APP_ICON_LOADER_H_
 
 #include <map>
 #include <memory>
 #include <string>
 
 #include "base/macros.h"
+#include "chrome/browser/extensions/extension_app_icon_delegate.h"
 #include "chrome/browser/ui/app_icon_loader.h"
-#include "extensions/browser/extension_icon_image.h"
 
 class Profile;
 
 namespace extensions {
 
 // Implementation of AppIconLoader that interacts with the ExtensionService and
 // ImageLoader to load images.
 class ExtensionAppIconLoader : public AppIconLoader,
-                               public extensions::IconImage::Observer {
+                               public ExtensionAppIconDelegate {
  public:
   ExtensionAppIconLoader(Profile* profile, int icon_size,
                          AppIconLoaderDelegate* delegate);
   ~ExtensionAppIconLoader() override;
 
   // AppIconLoader overrides:
   bool CanLoadImageForApp(const std::string& id) override;
   void FetchImage(const std::string& id) override;
   void ClearImage(const std::string& id) override;
   void UpdateImage(const std::string& id) override;
 
-  // extensions::IconImage::Observer overrides:
-  void OnExtensionIconImageChanged(extensions::IconImage* image) override;
-
  private:
   using ExtensionIDToImageMap =
-      std::map<std::string, std::unique_ptr<extensions::IconImage>>;
+      std::map<std::string, std::unique_ptr<ExtensionAppIcon>>;
 
-  // Builds image for given |id| and |icon|.
-  void BuildImage(const std::string& id, const gfx::ImageSkia& icon);
+  // ExtensionAppIconDelegate:
+  void UpdateIcon(ExtensionAppIcon* icon, const gfx::ImageSkia& image) override;
 
   // Maps from extension id to IconImage pointer.
   ExtensionIDToImageMap map_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionAppIconLoader);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_APP_ICON_LOADER_H_