diff --git a/core/modules/system/system.admin.inc b/core/modules/system/system.admin.inc
index 4dd7e5e..d3a2896 100644
--- a/core/modules/system/system.admin.inc
+++ b/core/modules/system/system.admin.inc
@@ -1868,7 +1868,7 @@ function system_date_format_localize_form_submit($form, &$form_state) {
   foreach ($formats as $date_format_id => $format_info) {
     if (isset($form_state['values']['date_format_' . $date_format_id])) {
       $format = $form_state['values']['date_format_' . $date_format_id];
-      system_date_format_localize_form_save($langcode, $format_info, $formats[$format]->get('pattern'));
+      system_date_format_localize_form_save($langcode, $date_format_id, $formats[$format]);
     }
   }
   drupal_set_message(t('Configuration saved.'));
@@ -1912,14 +1912,14 @@ function theme_system_date_format_localize_form($variables) {
  * @param string $langcode
  *   Language code, can be 2 characters, e.g. 'en' or 5 characters, e.g.
  *   'en-CA'.
- * @param \Drupal\system\DateFormatInterface $date_format
+ * @param string $date_format_id
+ *   Date format id, e.g. 'short', 'medium'.
+ * @param \Drupal\system\DateFormatInterface $format
  *   The date format entity.
- * @param string $format
- *   The date format string.
  */
-function system_date_format_localize_form_save($langcode, DateFormatInterface $date_format, $format) {
-  $date_format->addLocale($langcode)->save();
-  config('locale.config.' . $langcode . '.system.date_format.' . $date_format->id())
-    ->set('pattern', $format)
+function system_date_format_localize_form_save($langcode, $date_format_id, DateFormatInterface $format) {
+  $format->addLocale($langcode)->save();
+  config('locale.config.' . $langcode . '.system.date_format.' . $date_format_id)
+    ->set('pattern', $format->get('pattern'))
     ->save();
 }