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/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:
-  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>>;
-
-  // Builds image for given |id| and |icon|.
-  void BuildImage(const std::string& id, const gfx::ImageSkia& icon);
-
-  // 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_