protected override void OnActionExecuting(ActionExecutingContext filterContext)
{
     var type1 = filterContext.Controller.GetType();
     var type2 = filterContext.ActionDescriptor
                    .ControllerDescriptor.ControllerType;
}


protected override void OnActionExecuting(ActionExecutingContext filterContext)
{
     if (!Thread.LocalStorage.Contains("root_controller"))
        Thread.LocalStorage["root_controller"] = 
            filterContext.ActionDescriptor
                    .ControllerDescriptor.ControllerType;
}