diff -r c7c34916027a -r 177826044cd9 wp/wp-includes/customize/class-wp-widget-form-customize-control.php
--- a/wp/wp-includes/customize/class-wp-widget-form-customize-control.php	Mon Oct 14 18:06:33 2019 +0200
+++ b/wp/wp-includes/customize/class-wp-widget-form-customize-control.php	Mon Oct 14 18:28:13 2019 +0200
@@ -15,13 +15,68 @@
  * @see WP_Customize_Control
  */
 class WP_Widget_Form_Customize_Control extends WP_Customize_Control {
+	/**
+	 * Customize control type.
+	 *
+	 * @since 3.9.0
+	 * @var string
+	 */
 	public $type = 'widget_form';
+
+	/**
+	 * Widget ID.
+	 *
+	 * @since 3.9.0
+	 * @var string
+	 */
 	public $widget_id;
+
+	/**
+	 * Widget ID base.
+	 *
+	 * @since 3.9.0
+	 * @var string
+	 */
 	public $widget_id_base;
+
+	/**
+	 * Sidebar ID.
+	 *
+	 * @since 3.9.0
+	 * @var string
+	 */
 	public $sidebar_id;
+
+	/**
+	 * Widget status.
+	 *
+	 * @since 3.9.0
+	 * @var bool True if new, false otherwise. Default false.
+	 */
 	public $is_new = false;
+
+	/**
+	 * Widget width.
+	 *
+	 * @since 3.9.0
+	 * @var int
+	 */
 	public $width;
+
+	/**
+	 * Widget height.
+	 *
+	 * @since 3.9.0
+	 * @var int
+	 */
 	public $height;
+
+	/**
+	 * Widget mode.
+	 *
+	 * @since 3.9.0
+	 * @var bool True if wide, false otherwise. Default false.
+	 */
 	public $is_wide = false;
 
 	/**
@@ -41,7 +96,7 @@
 		}
 
 		// Get the widget_control and widget_content.
-		require_once ABSPATH . '/wp-admin/includes/widgets.php';
+		require_once ABSPATH . 'wp-admin/includes/widgets.php';
 
 		$widget = $wp_registered_widgets[ $this->widget_id ];
 		if ( ! isset( $widget['params'][0] ) ) {
@@ -49,11 +104,16 @@
 		}
 
 		$args = array(
-			'widget_id' => $widget['id'],
+			'widget_id'   => $widget['id'],
 			'widget_name' => $widget['name'],
 		);
 
-		$args = wp_list_widget_controls_dynamic_sidebar( array( 0 => $args, 1 => $widget['params'][0] ) );
+		$args                 = wp_list_widget_controls_dynamic_sidebar(
+			array(
+				0 => $args,
+				1 => $widget['params'][0],
+			)
+		);
 		$widget_control_parts = $this->manager->widgets->get_widget_control_parts( $args );
 
 		$this->json['widget_control'] = $widget_control_parts['control'];