context menu does not work if one already open

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 "build/build_config.h"
 
 #include <list>
@@ skipping 394 matching lines @@
 
   // Selects or accepts the appropriate menu item based on |details|. Returns
   // true if |Accept| was invoked (which happens if there aren't multiple item
   // with the same mnemonic and the item to select does not have a submenu).
   bool AcceptOrSelect(MenuItemView* parent, const SelectByCharDetails& details);
 
   // Selects by mnemonic, and if that doesn't work tries the first character of
   // the title. Returns true if a match was selected and the menu should exit.
   bool SelectByChar(char16 key);
 
-#if defined(OS_WIN) && !defined(USE_AURA)
+#if (defined(OS_WIN) && !defined(USE_AURA)) || defined(OS_CHROMEOS)
   // If there is a window at the location of the event, a new mouse event is
   // generated and posted to it at the given location.
+  // For Chromeos it applies also to the background window, i.e. always.
   void RepostEvent(SubmenuView* source, const ui::LocatedEvent& event);
 #endif
 
   // Sets the drop target to new_item.
   void SetDropMenuItem(MenuItemView* new_item,
                        MenuDelegate::DropPosition position);
 
   // Starts/stops scrolling as appropriate. part gives the part the mouse is
   // over.
   void UpdateScrolling(const MenuPart& part);
@@ skipping 124 matching lines @@
   int message_loop_depth_;
 
   views::MenuConfig menu_config_;
 
   DISALLOW_COPY_AND_ASSIGN(MenuController);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_MENU_MENU_CONTROLLER_H_