Index: src/wp-includes/widgets/class-wp-nav-menu-widget.php
===================================================================
--- src/wp-includes/widgets/class-wp-nav-menu-widget.php	(revision 34550)
+++ src/wp-includes/widgets/class-wp-nav-menu-widget.php	(working copy)
@@ -49,17 +49,20 @@
 		 * Filter the arguments for the Custom Menu widget.
 		 *
 		 * @since 4.2.0
+		 * @since 4.4.0 Added `$instance` and `$this` parameters.
 		 *
-		 * @param array    $nav_menu_args {
+		 * @param array              $nav_menu_args {
 		 *     An array of arguments passed to wp_nav_menu() to retrieve a custom menu.
 		 *
 		 *     @type callback|bool $fallback_cb Callback to fire if the menu doesn't exist. Default empty.
 		 *     @type mixed         $menu        Menu ID, slug, or name.
 		 * }
-		 * @param stdClass $nav_menu      Nav menu object for the current menu.
-		 * @param array    $args          Display arguments for the current widget.
+		 * @param stdClass           $nav_menu      Nav menu object for the current menu.
+		 * @param array              $args          Display arguments for the current widget.
+		 * @param array              $instance      Array of settings for the current widget.
+		 * @param WP_Nav_Menu_Widget $this          The nav menu widget instance.
 		 */
-		wp_nav_menu( apply_filters( 'widget_nav_menu_args', $nav_menu_args, $nav_menu, $args ) );
+		wp_nav_menu( apply_filters( 'widget_nav_menu_args', $nav_menu_args, $nav_menu, $args, $instance, $this ) );
 
 		echo $args['after_widget'];
 	}