Pause close timer of notification while it's active

ui/message_center/views/message_popup_collection.h

 // Copyright (c) 2013 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 UI_MESSAGE_CENTER_VIEWS_MESSAGE_POPUP_COLLECTION_H_
 #define UI_MESSAGE_CENTER_VIEWS_MESSAGE_POPUP_COLLECTION_H_
 
 #include <stddef.h>
 
 #include <list>
@@ skipping 54 matching lines @@
       const NotifierId& notifier_id,
       const base::string16& display_source) override;
   bool HasClickedListener(const std::string& notification_id) override;
   void ClickOnNotificationButton(const std::string& notification_id,
                                  int button_index) override;
   void ClickOnSettingsButton(const std::string& notification_id) override;
   void UpdateNotificationSize(const std::string& notification_id) override;
 
   void MarkAllPopupsShown();
 
+  // Inclement the timer counter, and pause the popup timer if necessary.
+  void PausePopupTimers();
+  // Declement the timer counter, and restart the popup timer if necessary.
+  void RestartPopupTimers();
+
   // Since these events are really coming from individual toast widgets,
   // it helps to be able to keep track of the sender.
   void OnMouseEntered(ToastContentsView* toast_entered);
   void OnMouseExited(ToastContentsView* toast_exited);
 
   // Invoked by toasts when they start/finish their animations.
   // While "defer counter" is greater than zero, the popup collection does
   // not perform updates. It is used to wait for various animations and user
   // actions like serial closing of the toasts, when the remaining toasts "flow
   // under the mouse".
@@ skipping 73 matching lines @@
   // sequence, w/o moving the mouse. We reposition the toasts so the next one
   // happens to be right under the mouse, and the user can just dispose of
   // multipel toasts by clicking. The mode ends when defer_timer_ expires.
   bool user_is_closing_toasts_by_clicking_;
   std::unique_ptr<base::OneShotTimer> defer_timer_;
   // The top edge to align the position of the next toast during 'close by
   // clicking" mode.
   // Only to be used when user_is_closing_toasts_by_clicking_ is true.
   int target_top_edge_;
 
+  // This is the number of pause request for timer. If it's more than zero, the
+  // timer is paused. If zero, the timer is not paused.
+  int timer_pause_counter_ = 0;
+
   // Weak, only exists temporarily in tests.
   std::unique_ptr<base::RunLoop> run_loop_for_test_;
 
   std::unique_ptr<MessageViewContextMenuController> context_menu_controller_;
 
   // Gives out weak pointers to toast contents views which have an unrelated
   // lifetime.  Must remain the last member variable.
   base::WeakPtrFactory<MessagePopupCollection> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MessagePopupCollection);
 };
 
 }  // namespace message_center
 
 #endif  // UI_MESSAGE_CENTER_VIEWS_MESSAGE_POPUP_COLLECTION_H_