REST API: Don't assume all item schemas have properties.

All schema types, not just objects, are permitted as the base type of a resource. A future patch could add validation support for those types, but this fix only prevents a PHP warning from being issued.

Props dhavalkasvala, johnwatkins0, birgire.
Fixes #48785.

Built from https://develop.svn.wordpress.org/trunk@47328


git-svn-id: http://core.svn.wordpress.org/trunk@47122 1a063a9b-81f0-0310-95a4-ce76da25c4cd

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

@@ -344,9 +344,11 @@ abstract class WP_REST_Controller {
 
 		$schema = $this->get_item_schema();
 
+		if ( ! empty( $schema['properties'] ) ) {
 			foreach ( $schema['properties'] as &$property ) {
 				unset( $property['arg_options'] );
 			}
+		}
 
 		return $schema;
 	}

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.4-beta2-47327';
+$wp_version = '5.4-beta2-47328';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.