Add WebNotificationTray

ash/shell.h

Index: ash/shell.h
diff --git a/ash/shell.h b/ash/shell.h
index 84f8d5d45b66aac6384f592f7afe5f81967fe5e9..01662d8ca1c037a3b71f3284255fa049cc2a9daa 100644
--- a/ash/shell.h
+++ b/ash/shell.h
@@ -73,6 +73,7 @@ class SystemTray;
 class UserActivityDetector;
 class UserWallpaperDelegate;
 class VideoDetector;
+class WebNotificationTray;
 class WindowCycleController;
 
 namespace internal {
@@ -266,7 +267,7 @@ class ASH_EXPORT Shell : aura::CursorDelegate {
   }
 
   ShellDelegate* delegate() { return delegate_.get(); }
-  SystemTrayDelegate* tray_delegate() { return tray_delegate_.get(); }
+
   UserWallpaperDelegate* user_wallpaper_delegate() {
     return user_wallpaper_delegate_.get();
   }
@@ -304,7 +305,10 @@ class ASH_EXPORT Shell : aura::CursorDelegate {
     return status_area_widget_;
   }
 
-  SystemTray* system_tray() const { return system_tray_.get(); }
+  // Convenience accessor for members of StatusAreaWidget.
+  // TODO(stevenjb): remove these and move code to StatusAreaWidget instead.
+  SystemTrayDelegate* tray_delegate();
+  SystemTray* system_tray();
 
   // Returns the size of the grid.
   int GetGridSize() const;
@@ -384,7 +388,6 @@ class ASH_EXPORT Shell : aura::CursorDelegate {
 #endif  // !defined(OS_MACOSX)
 
   scoped_ptr<ShellDelegate> delegate_;
-  scoped_ptr<SystemTrayDelegate> tray_delegate_;
   scoped_ptr<UserWallpaperDelegate> user_wallpaper_delegate_;
 
   scoped_ptr<Launcher> launcher_;
@@ -459,12 +462,9 @@ class ASH_EXPORT Shell : aura::CursorDelegate {
   // Owned by aura::RootWindow, cached here for type safety.
   internal::RootWindowLayoutManager* root_window_layout_;
 
-  // Widget containing system tray.
+  // Widget containing system tray and web notification tray.
   internal::StatusAreaWidget* status_area_widget_;
 
-  // System tray with clock, Wi-Fi signal, etc.
-  scoped_ptr<SystemTray> system_tray_;
-
   // Used by ash/shell.
   content::BrowserContext* browser_context_;