fixed

Closes #3320825

src/EntityReferenceRevisionsFieldItemList.php

@@ -18,7 +18,7 @@ class EntityReferenceRevisionsFieldItemList extends EntityReferenceFieldItemList
   /**
    * {@inheritdoc}
    */
-  public function referencedEntities() {
+  public function referencedEntities(?string $langcode = NULL) {
     if (empty($this->list)) {
       return array();
     }