diff --git a/core/modules/system/src/Tests/Form/ExternalFormUrlTest.php b/core/modules/system/src/Tests/Form/ExternalFormUrlTest.php
index df3544c..87c7420 100644
--- a/core/modules/system/src/Tests/Form/ExternalFormUrlTest.php
+++ b/core/modules/system/src/Tests/Form/ExternalFormUrlTest.php
@@ -64,13 +64,14 @@ protected function setUp() {
     parent::setUp();
     $this->installSchema('system', ['key_value_expire', 'sequences']);
     $this->installEntitySchema('user');
-    $this->logger = \Drupal::logger('test_logger');
+
     $test_user = User::create(array(
       'name' => 'foobar',
       'mail' => 'foobar@example.com',
     ));
     $test_user->save();
     \Drupal::service('current_user')->setAccount($test_user);
+
     // Create a new request and make it the master request.
     $request_stack = \Drupal::service('request_stack');
     $original_request = $request_stack->pop();
@@ -82,16 +83,16 @@ protected function setUp() {
    * Tests form behaviour.
    */
   public function testExternalUrlBehavior() {
-    $form_state = new FormState();
-    $form_state->setCached();
-    $form_builder = $this->container->get('form_builder');
-    $form = $form_builder->getForm(get_class($this));
-    $markup = \Drupal::service('renderer')->render($form);
+    $form = \Drupal::formBuilder()->getForm(get_class($this));
+    $markup = \Drupal::service('renderer')->renderRoot($form);
+
     $dom = new \DOMDocument();
     $dom->loadXML($markup);
+
     $xpath = new \DOMXPath($dom);
     $form = $xpath->query('//form');
     $action = $form->item(0)->getAttribute('action');
+
     $this->assertNotEqual('//example.org', $action);
     $this->assertEqual('/example.org', $action);
   }