Refactor extension app icon.

chrome/browser/extensions/chrome_app_icon.h

+// Copyright 2017 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_CHROME_APP_ICON_H_
+#define CHROME_BROWSER_EXTENSIONS_CHROME_APP_ICON_H_
+
+#include <memory>
+#include <string>
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "extensions/browser/extension_icon_image.h"
+#include "ui/gfx/image/image_skia.h"
+
+namespace content {
+class BrowserContext;
+}
+
+namespace extensions {
+
+class Extension;
+class ChromeAppIconDelegate;
+
+// This represents how an extension app icon should finally look. As a base,
+// extension icon is used and effects that depend on extension type, state and
+// some external conditions are applied. Resulting image is sent via
+// ChromeAppIconDelegate. Several updates are expected in case extension
+// state or some external conditions are changed.
+class ChromeAppIcon : public IconImage::Observer {
+ public:
+  using DestroyedCallback = base::OnceCallback<void(ChromeAppIcon*)>;
+
+  ChromeAppIcon(ChromeAppIconDelegate* delegate,
+                content::BrowserContext* browser_context,
+                DestroyedCallback destroyed_callback,
+                const std::string& app_id,
+                int resource_size_in_dip);
+  ~ChromeAppIcon() override;
+
+  // Reloads icon.
+  void Reload();
+
+  // Returns true if the icon still refers to existing extension. Once extension
+  // is disabled it is discarded from the icon.
+  bool IsValid() const;
+
+  // Re-applies app effects over the current extension icon and dispatches the
+  // result via |delegate_|.
+  void UpdateIcon();
+
+  const gfx::ImageSkia& image_skia() const { return image_skia_; }
+  const std::string& app_id() const { return app_id_; }
+
+ private:
+  const Extension* GetExtension();
+
+  // IconImage::Observer:
+  void OnExtensionIconImageChanged(IconImage* image) override;
+
+  // Unowned pointers.
+  ChromeAppIconDelegate* const delegate_;
+  content::BrowserContext* const browser_context_;
+
+  // Called when this instance of ChromeAppIcon is destroyed.
+  DestroyedCallback destroyed_callback_;
+
+  const std::string app_id_;
+
+  // Contains current icon image. This is static image with applied effects and
+  // it is updated each time when |icon_| is updated.
+  gfx::ImageSkia image_skia_;
+
+  const int resource_size_in_dip_;
+
+  std::unique_ptr<IconImage> icon_;
+
+  DISALLOW_COPY_AND_ASSIGN(ChromeAppIcon);
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_CHROME_APP_ICON_H_