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

ui/base/models/simple_menu_model.h

Index: ui/base/models/simple_menu_model.h
diff --git a/ui/base/models/simple_menu_model.h b/ui/base/models/simple_menu_model.h
index e8ccb40afec92d21af4767801331d60381f45c60..c3f53683fe247f6a5218fa0330c2724dbbd78b5f 100644
--- a/ui/base/models/simple_menu_model.h
+++ b/ui/base/models/simple_menu_model.h
@@ -48,6 +48,7 @@ class SimpleMenuModel : public MenuModel {
 
     // Performs the action associated with the specified command id.
     virtual void ExecuteCommand(int command_id) = 0;
+    virtual void ExecuteCommandWithFlags(int command_id, int flags);
 
     // Notifies the delegate that the menu is about to show.
     virtual void MenuWillShow();
@@ -122,6 +123,8 @@ class SimpleMenuModel : public MenuModel {
   virtual bool IsVisibleAt(int index) const OVERRIDE;
   virtual void HighlightChangedTo(int index) OVERRIDE;
   virtual void ActivatedAt(int index) OVERRIDE;
+  virtual void ActivatedAtWithFlags(int index, int flags) OVERRIDE;
+
   virtual MenuModel* GetSubmenuModelAt(int index) const OVERRIDE;
   virtual void MenuWillShow() OVERRIDE;
   virtual void MenuClosed() OVERRIDE;