REST API: Ensure a sidebar's widgets property is a list.

When a widget is removed from a sidebar, if it was removed from the middle of the list, the widgets property would become an object with numeric keys.

The sidebars controller now forces the widgets property to be a list.

Props walbo.
Fixes #53612.

Built from https://develop.svn.wordpress.org/trunk@51377


git-svn-id: http://core.svn.wordpress.org/trunk@50988 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/rest-api/endpoints/class-wp-rest-sidebars-controller.php

@@ -304,7 +304,7 @@ class WP_REST_Sidebars_Controller extends WP_REST_Controller {
 				}
 			);
 
-			$sidebar['widgets'] = $widgets;
+			$sidebar['widgets'] = array_values( $widgets );
 		}
 
 		$schema = $this->get_item_schema();

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.9-alpha-51375';
+$wp_version = '5.9-alpha-51377';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.