Laravel show 404 in a layout view

//original source unknown
<?php

App::error(function(Exception $exception, $code) {

    if ($exception instanceof \Symfony\Component\HttpKernel\Exception\NotFoundHttpException) {
      Log::error('NotFoundHttpException Route: ' . Request::url() );
    }

    Log::error($exception);

    // HTML output on staging and production only
    if (!Config::get('app.debug'))
        return App::make("ErrorsController")->callAction("error", ['code'=>$code]);
});

//errors controller

<?php

class ErrorsController extends BaseController {

    protected $layout = "layouts.frontend";

    public function error($code) {
        switch ($code) {
            case 404:
                $this->layout->content = View::make('errors.404');
            break;

            default:
                $this->layout->content = View::make('errors.500');
            break;
        }
    }
}