diff -r c7c34916027a -r 177826044cd9 wp/wp-includes/class-walker-page-dropdown.php
--- a/wp/wp-includes/class-walker-page-dropdown.php	Mon Oct 14 18:06:33 2019 +0200
+++ b/wp/wp-includes/class-walker-page-dropdown.php	Mon Oct 14 18:28:13 2019 +0200
@@ -35,7 +35,10 @@
 	 * @see Walker::$db_fields
 	 * @todo Decouple this
 	 */
-	public $db_fields = array( 'parent' => 'post_parent', 'id' => 'ID' );
+	public $db_fields = array(
+		'parent' => 'post_parent',
+		'id'     => 'ID',
+	);
 
 	/**
 	 * Starts the element output.
@@ -54,15 +57,16 @@
 	 * @param int     $id     Optional. ID of the current page. Default 0 (unused).
 	 */
 	public function start_el( &$output, $page, $depth = 0, $args = array(), $id = 0 ) {
-		$pad = str_repeat(' ', $depth * 3);
+		$pad = str_repeat( ' ', $depth * 3 );
 
 		if ( ! isset( $args['value_field'] ) || ! isset( $page->{$args['value_field']} ) ) {
 			$args['value_field'] = 'ID';
 		}
 
-		$output .= "\t<option class=\"level-$depth\" value=\"" . esc_attr( $page->{$args['value_field']} ) . "\"";
-		if ( $page->ID == $args['selected'] )
+		$output .= "\t<option class=\"level-$depth\" value=\"" . esc_attr( $page->{$args['value_field']} ) . '"';
+		if ( $page->ID == $args['selected'] ) {
 			$output .= ' selected="selected"';
+		}
 		$output .= '>';
 
 		$title = $page->post_title;
@@ -76,8 +80,8 @@
 		 *
 		 * @since 3.1.0
 		 *
-		 * @param string $title Page title.
-		 * @param object $page  Page data object.
+		 * @param string  $title Page title.
+		 * @param WP_Post $page  Page data object.
 		 */
 		$title = apply_filters( 'list_pages', $title, $page );