Add message to Ash message center for no notifications

ash/system/status_area_widget.cc

 // Copyright (c) 2012 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.
 
 #include "ash/system/status_area_widget.h"
 
 #include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "ash/shell_window_ids.h"
@@ skipping 307 matching lines @@
   system_tray_->Initialize();  // Called after added to widget.
 
   if (shell_delegate) {
     system_tray_delegate_.reset(
         shell_delegate->CreateSystemTrayDelegate(system_tray));
   }
   if (!system_tray_delegate_.get())
     system_tray_delegate_.reset(new DummySystemTrayDelegate());
 
   system_tray->CreateItems();  // Called after delegate is created.
+  UpdateAfterLoginStatusChange(system_tray_delegate_->GetUserLoginStatus());
 }
 
 void StatusAreaWidget::AddWebNotificationTray(
     WebNotificationTray* web_notification_tray) {
   web_notification_tray_ = web_notification_tray;
   widget_delegate_->AddTray(web_notification_tray);
 }
 
 void StatusAreaWidget::SetShelfAlignment(ShelfAlignment alignment) {
   widget_delegate_->set_alignment(alignment);
@@ skipping 22 matching lines @@
   if (system_tray_)
     system_tray_->SetHideNotifications(hide);
 }
 
 bool StatusAreaWidget::ShouldShowNonSystemNotifications() {
   return !(system_tray_ && system_tray_->IsAnyBubbleVisible());
 }
 
 void StatusAreaWidget::UpdateAfterLoginStatusChange(
     user::LoginStatus login_status) {
+  if (login_status_ == login_status)
+    return;
   login_status_ = login_status;
   if (system_tray_)
     system_tray_->UpdateAfterLoginStatusChange(login_status);
   if (web_notification_tray_)
     web_notification_tray_->UpdateAfterLoginStatusChange(login_status);
 }
 
 }  // namespace internal
 }  // namespace ash