void GoToBase(object sender, EventArgs e)
        {
            MenuCommand item       = (MenuCommand)sender;
            IMember     member     = (IMember)item.Tag;
            IMember     baseMember = RefactoringService.FindBaseMember(member);

            if (baseMember != null)
            {
                FindReferencesAndRenameHelper.JumpToDefinition(baseMember);
            }
        }