diff --git a/core/modules/user/src/Tests/UserUsernameTest.php b/core/modules/user/src/Tests/UserUsernameTest.php
index e6573a3..73ec68c 100644
--- a/core/modules/user/src/Tests/UserUsernameTest.php
+++ b/core/modules/user/src/Tests/UserUsernameTest.php
@@ -9,6 +9,7 @@
 
 use Drupal\Component\Utility\String;
 use Drupal\Component\Utility\Unicode;
+use Drupal\comment\Tests\CommentTestTrait;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -18,6 +19,8 @@
  */
 class UserUsernameTest extends WebTestBase {
 
+  use CommentTestTrait;
+
   /**
    * Modules to enable.
    *
@@ -50,8 +53,8 @@ class UserUsernameTest extends WebTestBase {
   public function setUp() {
     parent::setUp();
 
-    $this->drupalCreateContentType(array('type' => 'article'));
-    $this->container->get('comment.manager')->addDefaultField('node', 'article');
+    $this->drupalCreateContentType(array('type' => 'article', 'name' => 'Article'));
+    $this->addDefaultCommentField('node', 'article');
 
     // Create user with short username.
     $this->userShortName = $this->drupalCreateUser(