cheets: implement cros side of WallpaperManagerService.

chrome/browser/chromeos/arc/arc_service_launcher.h

Index: chrome/browser/chromeos/arc/arc_service_launcher.h
diff --git a/chrome/browser/chromeos/arc/arc_service_launcher.h b/chrome/browser/chromeos/arc/arc_service_launcher.h
index 7d912bbb5dc1bfcd7f89bd5841e078a36949af1a..abc5b3966b9b42812321ee3f99c5cb279561cf92 100644
--- a/chrome/browser/chromeos/arc/arc_service_launcher.h
+++ b/chrome/browser/chromeos/arc/arc_service_launcher.h
@@ -12,6 +12,8 @@
 
 namespace arc {
 
+class ArcWallpaperHandler;
+
 // Detects ARC availability and launches ARC bridge service.
 class ArcServiceLauncher {
  public:
@@ -23,6 +25,7 @@ class ArcServiceLauncher {
 
  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);
 };