Do not show notifications when in fullscreen or screensaver mode....

chrome/browser/notifications/notification_ui_manager.h

 // Copyright (c) 2009 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.
 
 #ifndef CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_UI_MANAGER_H_
 #define CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_UI_MANAGER_H_
 #pragma once
 
 #include <deque>
 #include <string>
 
 #include "base/id_map.h"
 #include "base/scoped_ptr.h"
+#include "base/timer.h"
 #include "chrome/browser/notifications/balloon.h"
 #include "chrome/browser/notifications/balloon_collection.h"
 #include "chrome/browser/prefs/pref_member.h"
 #include "chrome/common/notification_observer.h"
 #include "chrome/common/notification_registrar.h"
 
 class Notification;
 class PrefService;
 class Profile;
 class QueuedNotification;
@@ skipping 62 matching lines @@
   // Attempts to display notifications from the show_queue.
   void ShowNotifications();
 
   // BalloonCollectionObserver implementation.
   virtual void OnBalloonSpaceChanged();
 
   // Replace an existing notification with this one if applicable;
   // returns true if the replacement happened.
   bool TryReplacement(const Notification& notification);
 
+  // Checks the user state to decide if we want to show the notification.
+  void CheckUserState();
+
   // An owned pointer to the collection of active balloons.
   scoped_ptr<BalloonCollection> balloon_collection_;
 
   // A queue of notifications which are waiting to be shown.
   typedef std::deque<QueuedNotification*> NotificationDeque;
   NotificationDeque show_queue_;
 
   // Registrar for the other kind of notifications (event signaling).
   NotificationRegistrar registrar_;
 
   // Prefs listener for the position preference.
   IntegerPrefMember position_pref_;
 
+  // Used by screen-saver and full-screen handling support.
+  bool is_user_active_;
+  base::RepeatingTimer<NotificationUIManager> user_state_check_timer_;
+
   DISALLOW_COPY_AND_ASSIGN(NotificationUIManager);
 };
 
 #endif  // CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_UI_MANAGER_H_