Walker_Comment::end_el

	 * @see Walker::end_el()
	 * @see wp_list_comments()
	 *
	 * @param string     $output  Used to append additional content. Passed by reference.
	 * @param WP_Comment $comment The current comment object. Default current comment.
	 * @param int        $depth   Optional. Depth of the current comment. Default 0.
	 * @param array      $args    Optional. An array of arguments. Default empty array.
	 */
	public function end_el( &$output, $comment, $depth = 0, $args = array() ) {
		if ( ! empty( $args['end-callback'] ) ) {
			ob_start();
			call_user_func( $args['end-callback'], $comment, $args, $depth );
			$output .= ob_get_clean();