Send notification to users upon receiving sms messages

ash/common/shelf/shelf_widget.h

Index: ash/common/shelf/shelf_widget.h
diff --git a/ash/common/shelf/shelf_widget.h b/ash/common/shelf/shelf_widget.h
index 995ef8ce17be269da93adfef3a72653eda4ec652..87f493baa9c0b6efc97f4dc44c0992d920dd565b 100644
--- a/ash/common/shelf/shelf_widget.h
+++ b/ash/common/shelf/shelf_widget.h
@@ -25,10 +25,15 @@ class AppListButton;
 class FocusCycler;
 class ShelfLayoutManager;
 class ShelfView;
+class SmsObserver;
 class StatusAreaWidget;
 class WmShelf;
 class WmWindow;
 
+namespace test {
+class SmsObserverTest;
+}
+
 // The ShelfWidget manages the shelf view (which contains the shelf icons) and
 // the status area widget. There is one ShelfWidget per display. It is created
 // early during RootWindowController initialization.
@@ -103,6 +108,7 @@ class ASH_EXPORT ShelfWidget : public views::Widget,
  private:
   class DelegateView;
   friend class DelegateView;
+  friend class ash::test::SmsObserverTest;
 
   WmShelf* wm_shelf_;
 
@@ -119,6 +125,7 @@ class ASH_EXPORT ShelfWidget : public views::Widget,
   // at the login screen.
   ShelfView* shelf_view_;
   ShelfBackgroundAnimator background_animator_;
+  std::unique_ptr<SmsObserver> sms_observer_;
   bool activating_as_fallback_;
 
   DISALLOW_COPY_AND_ASSIGN(ShelfWidget);