Send notification to users upon receiving sms messages

ash/shell.h

Index: ash/shell.h
diff --git a/ash/shell.h b/ash/shell.h
index 33b7ed6e70f5fb05ce3bef8a93a02e6bb6f7a0f5..8731782e48cc45a22831e3edb4bffa2921505c6c 100644
--- a/ash/shell.h
+++ b/ash/shell.h
@@ -109,6 +109,7 @@ class ScreenPositionController;
 class SessionStateDelegate;
 struct ShellInitParams;
 class ShutdownObserver;
+class SmsObserver;
 class StickyKeysController;
 class SystemGestureEventFilter;
 class SystemModalContainerEventFilter;
@@ -131,6 +132,7 @@ class WindowWatcher;
 
 namespace test {
 class ShellTestApi;
+class SmsObserverTest;
 }
 
 // Shell is a singleton object that presents the Shell API and implements the
@@ -407,6 +409,7 @@ class ASH_EXPORT Shell : public SystemModalContainerEventFilterDelegate,
   friend class RootWindowController;
   friend class test::ShellTestApi;
   friend class shell::WindowWatcher;
+  friend class SmsObserverTest;
 
   explicit Shell(std::unique_ptr<WmShell> wm_shell);
   ~Shell() override;
@@ -526,6 +529,9 @@ class ASH_EXPORT Shell : public SystemModalContainerEventFilterDelegate,
   // Listens for shutdown and updates DisplayConfigurator.
   std::unique_ptr<ShutdownObserver> shutdown_observer_;
 
+  // Listens for new sms messages and shows notifications.
+  std::unique_ptr<SmsObserver> sms_observer_;
+
   // Implements content::ScreenOrientationController for Chrome OS.
   std::unique_ptr<ScreenOrientationController> screen_orientation_controller_;
   std::unique_ptr<ScreenLayoutObserver> screen_layout_observer_;