Change MenuControllerDelegate to provide WeakPtr

ui/views/controls/menu/menu_controller.h

 // 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.
 
 #ifndef UI_VIEWS_CONTROLS_MENU_MENU_CONTROLLER_H_
 #define UI_VIEWS_CONTROLS_MENU_MENU_CONTROLLER_H_
 
 #include <stddef.h>
 
 #include <list>
@@ skipping 588 matching lines @@
   // If not empty, it means we're nested. When Run is invoked from within
   // Run, the current state (state_) is pushed onto menu_stack_. This allows
   // MenuController to restore the state when the nested run returns.
   using NestedState =
       std::pair<State, std::unique_ptr<MenuButton::PressedLock>>;
   std::list<NestedState> menu_stack_;
 
   // When Run is invoked during an active Run, it may be called from a separate
   // MenuControllerDelegate. If not empty is means we are nested, and the
   // stacked delegates should be notified instead of |delegate_|.
-  typedef std::pair<internal::MenuControllerDelegate*, bool> NestedDelegate;
+  typedef std::pair<base::WeakPtr<internal::MenuControllerDelegate>, bool>
+      NestedDelegate;
   std::list<NestedDelegate> delegate_stack_;
 
   // As the mouse moves around submenus are not opened immediately. Instead
   // they open after this timer fires.
   base::OneShotTimer show_timer_;
 
   // Used to invoke CancelAll(). This is used during drag and drop to hide the
   // menu after the mouse moves out of the of the menu. This is necessitated by
   // the lack of an ability to detect when the drag has completed from the drop
   // side.
@@ skipping 37 matching lines @@
   // The lock to keep the menu button pressed while a menu is visible.
   std::unique_ptr<MenuButton::PressedLock> pressed_lock_;
 
   // ViewStorage id used to store the view mouse drag events are forwarded to.
   // See UpdateActiveMouseView() for details.
   const int active_mouse_view_id_;
 
   // Current hot tracked child button if any.
   CustomButton* hot_button_;
 
-  internal::MenuControllerDelegate* delegate_;
+  base::WeakPtr<internal::MenuControllerDelegate> delegate_;
 
   // How deep we are in nested message loops. This should be at most 2 (when
   // showing a context menu from a menu).
   int message_loop_depth_;
 
   // The timestamp of the event which closed the menu - or 0 otherwise.
   base::TimeTicks closing_event_time_;
 
   // Time when the menu is first shown.
   base::TimeTicks menu_start_time_;
@@ skipping 27 matching lines @@
 #if defined(USE_AURA)
   std::unique_ptr<MenuPreTargetHandler> menu_pre_target_handler_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(MenuController);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_MENU_MENU_CONTROLLER_H_