diff --git a/core/tests/Drupal/Tests/Core/Form/FormSubmitterTest.php b/core/tests/Drupal/Tests/Core/Form/FormSubmitterTest.php
index ae71448..e1c9462 100644
--- a/core/tests/Drupal/Tests/Core/Form/FormSubmitterTest.php
+++ b/core/tests/Drupal/Tests/Core/Form/FormSubmitterTest.php
@@ -227,7 +227,7 @@ public function testExecuteSubmitHandlers() {
     // Methods directly on the form object can be specified as a string.
     $form_state = new FormState();
     $form_state['build_info']['callback_object'] = $mock;
-    $form_state['submit_handlers'][] = 'simple_string_submit';
+    $form_state['submit_handlers'][] = '::simple_string_submit';
     $form_submitter->executeSubmitHandlers($form, $form_state);
   }