diff --git a/core/modules/field_ui/lib/Drupal/field_ui/OverviewBase.php b/core/modules/field_ui/lib/Drupal/field_ui/OverviewBase.php
index c56ac96..7ea8391 100644
--- a/core/modules/field_ui/lib/Drupal/field_ui/OverviewBase.php
+++ b/core/modules/field_ui/lib/Drupal/field_ui/OverviewBase.php
@@ -46,9 +46,9 @@
    * {@inheritdoc}
    */
   public function buildForm(array $form, array &$form_state, $entity_type = NULL, $bundle = NULL) {
-    // Seriously, I hate comment module.
-    if ($entity_type == 'comment') {
-      $bundle = "comment_node_$bundle";
+    // @todo Comment has its own magical bundle naming.
+    if ($entity_type == 'comment' && module_exists('comment')) {
+      $bundle = comment_node_type_load($bundle);
     }
 
     form_load_include($form_state, 'inc', 'field_ui', 'field_ui.admin');
diff --git a/core/modules/file/lib/Drupal/file/Tests/FileFieldWidgetTest.php b/core/modules/file/lib/Drupal/file/Tests/FileFieldWidgetTest.php
index 654859f..8268999 100644
--- a/core/modules/file/lib/Drupal/file/Tests/FileFieldWidgetTest.php
+++ b/core/modules/file/lib/Drupal/file/Tests/FileFieldWidgetTest.php
@@ -205,6 +205,7 @@ function testPrivateFileSetting() {
     $type_name = 'article';
     $field_name = strtolower($this->randomName());
     $this->createFileField($field_name, $type_name);
+    $instance = field_info_instance('node', $field_name, $type_name);
 
     $test_file = $this->getTestFile('text');