cheets: implement cros side of WallpaperManagerService.

chrome/browser/chromeos/arc/arc_service_launcher.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_CHROMEOS_ARC_ARC_SERVICE_LAUNCHER_H_
 #define CHROME_BROWSER_CHROMEOS_ARC_ARC_SERVICE_LAUNCHER_H_
 
 #include <memory>
 
 #include "base/macros.h"
 #include "components/arc/arc_service_manager.h"
 
 namespace arc {
 
+class ArcWallpaperHandler;
+
 // Detects ARC availability and launches ARC bridge service.
 class ArcServiceLauncher {
  public:
   ArcServiceLauncher();
   ~ArcServiceLauncher();
 
   void Initialize();
   void Shutdown();
 
  private:
   std::unique_ptr<ArcServiceManager> arc_service_manager_;
+  std::shared_ptr<ArcWallpaperHandler> arc_wallpaper_handler_;

[xiyuan, 2016/08/22 22:49:41]

Do we really need a shared_ptr? Can some class own ArcWallpaperHandler and
provide access to its instance?

[Muyuan, 2016/08/22 23:48:19]

OK.. So I wonder if ArcServiceManager should own it?

[xiyuan, 2016/08/23 00:41:04]

Could it still be owned by ArcIntentHelperBridge as before? Where else do you
need to access it?

[Shuhei Takahashi, 2016/08/23 09:34:21]

ArcWallpaperHandler is accessed from ArcIntentHelperBridge and
ArcWallpaperBridge so it can't be owned by ArcIntentHelperBridge.

That said, please make this std::unique_ptr and pass a raw (borrowed) pointer to
ArcIntentHelperBridge/ArcWallpaperBridge. It is safe because ArcServiceLauncher
is guaranteed to outlive ArcServices. Please avoid std::shared_ptr as far as
possible since it makes it harder to reason about the timing and the thread of
destruction.

[Muyuan, 2016/08/23 19:45:48]

ArcWallpaperBridge

[Muyuan, 2016/08/23 19:45:48]

Done.

 
   DISALLOW_COPY_AND_ASSIGN(ArcServiceLauncher);
 };
 
 }  // namespace arc
 
 #endif  // CHROME_BROWSER_CHROMEOS_ARC_ARC_SERVICE_LAUNCHER_H_