added CTRL+Click and SHIFT+Click handler for context menu, Back and Forward.

ui/base/models/menu_model.h

 // Copyright (c) 2011 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_BASE_MODELS_MENU_MODEL_H_
 #define UI_BASE_MODELS_MENU_MODEL_H_
 #pragma once
 
 #include "base/memory/scoped_ptr.h"
 #include "base/string16.h"
@@ skipping 90 matching lines @@
   // Returns the model for the submenu at the specified index.
   virtual MenuModel* GetSubmenuModelAt(int index) const = 0;
 
   // Called when the highlighted menu item changes to the item at the specified
   // index.
   virtual void HighlightChangedTo(int index) = 0;
 
   // Called when the item at the specified index has been activated.
   virtual void ActivatedAt(int index) = 0;
 
-  // Called when the item has been activated with a given disposition (for the
-  // case where the activation involves a navigation).
-  virtual void ActivatedAtWithDisposition(int index, int disposition);
+  // Called when the item has been activated with an event flags.

[Ben Goodger (Google), 2011/05/31 16:00:00]

I would note here what flags are... is there a place where the possible values
are enumerated?

[shinyak (Google), 2011/06/09 02:29:04]

Done.

+  virtual void ActivatedAtWithFlags(int index, int flags);
 
   // Called when the menu is about to be shown.
   virtual void MenuWillShow() {}
 
   // Called when the menu has been closed.
   virtual void MenuClosed() {}
 
   // Set the MenuModelDelegate. Owned by the caller of this function.
   virtual void SetMenuModelDelegate(MenuModelDelegate* delegate) = 0;
 
   // Retrieves the model and index that contains a specific command id. Returns
   // true if an item with the specified command id is found. |model| is inout,
   // and specifies the model to start searching from.
   static bool GetModelAndIndexForCommandId(int command_id, MenuModel** model,
                                            int* index);
 };
 
 }  // namespace ui
 
 #endif  // UI_BASE_MODELS_MENU_MODEL_H_