Ticket #15808: 15808.diff

wp-includes/nav-menu-template.php

@@ -73 +73 @@
                 $classes = empty( $item->classes ) ? array() : (array) $item->classes;
                 $classes[] = 'menu-item-' . $item->ID;
 
-                $class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item ) );
+                $class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args ) );
                 $class_names = ' class="' . esc_attr( $class_names ) . '"';
 
                 $id = apply_filters( 'nav_menu_item_id', 'menu-item-'. $item->ID, $item, $args );