diff -Naur wp-includes/rest-api.php wp-includes/rest-api.php
--- wp-includes/rest-api.php	2018-12-05 12:21:27.576790000 +0530
+++ wp-includes/rest-api.php	2018-12-05 12:25:45.045654845 +0530
@@ -1247,7 +1247,7 @@
  *
  * @param mixed $value The value to sanitize.
  * @param array $args  Schema array to use for sanitization.
- * @return true|WP_Error
+ * @return array|int|float|boolean|string Based on args type it will return value.
  */
 function rest_sanitize_value_from_schema( $value, $args ) {
 	if ( 'array' === $args['type'] ) {