diff --git a/core/modules/field_ui/src/Form/FieldStorageConfigEditForm.php b/core/modules/field_ui/src/Form/FieldStorageConfigEditForm.php
index 8e8a0d8..58c4ea9 100644
--- a/core/modules/field_ui/src/Form/FieldStorageConfigEditForm.php
+++ b/core/modules/field_ui/src/Form/FieldStorageConfigEditForm.php
@@ -39,6 +39,9 @@ public function getEntityFromRouteMatch(RouteMatchInterface $route_match, $entit
 
   /**
    * {@inheritdoc}
+   *
+   * @param string $field_config
+   *   The ID of the field config whose field storage config is being edited.
    */
   public function buildForm(array $form, FormStateInterface $form_state, $field_config = NULL) {
     if ($field_config) {
@@ -77,7 +80,11 @@ public function form(array $form, FormStateInterface $form_state) {
     );
     // Create an arbitrary entity object, so that we can have an instantiated
     // FieldItem.
-    $ids = (object) array('entity_type' => $form_state->get('entity_type_id'), 'bundle' => $form_state->get('bundle'), 'entity_id' => NULL);
+    $ids = (object) array(
+      'entity_type' => $form_state->get('entity_type_id'),
+      'bundle' => $form_state->get('bundle'),
+      'entity_id' => NULL
+    );
     $entity = _field_create_entity_from_ids($ids);
     $items = $entity->get($this->entity->getName());
     $item = $items->first() ?: $items->appendItem();