only in patch2:
unchanged:
--- a/core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueContentEntityStorage.php
+++ b/core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueContentEntityStorage.php
@@ -13,7 +13,7 @@ class KeyValueContentEntityStorage extends KeyValueEntityStorage implements Cont
   /**
    * {@inheritdoc}
    */
-  public function createTranslation(ContentEntityInterface $entity, $langcode, array $values = []) {
+  public function createTranslation(ContentEntityInterface $entity, $langcode, array $values = [], $src_langcode = NULL) {
     // @todo Complete the content entity storage implementation in
     //   https://www.drupal.org/node/2618436.
   }