Fix popup crash on ChromeOS.

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 <list>
 #include <map>
 
@@ skipping 50 matching lines @@
   // |parent| specifies the parent widget of the toast windows. The default
   // parent will be used for NULL. Usually each icon is spacing against its
   // predecessor. If |first_item_has_no_margin| is set however the first item
   // does not space against the tray.
   MessagePopupCollection(gfx::NativeView parent,
                          MessageCenter* message_center,
                          MessageCenterTray* tray,
                          bool first_item_has_no_margin);
   virtual ~MessagePopupCollection();
 
+  void MarkAllPopupsShown();
+
   // 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 then 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 118 matching lines @@
   // 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_