Merge pull request #1734 from WP-API/1733-filter-array

Only process `filter` when it's an array

Author: danielbachhuber

lib/endpoints/class-wp-rest-posts-controller.php

@@ -89,7 +89,7 @@ public function get_items( $request ) {
 $args['paged'] = $request['page'];
 $args['posts_per_page'] = $request['per_page'];
 
-if ( isset( $request['filter'] ) ) {
+if ( is_array( $request['filter'] ) ) {
 $args = array_merge( $args, $request['filter'] );
 unset( $args['filter'] );
 }