Issue #2935256 follow-up by alexpott: Remove all usages of drupal_get_message...

Issue #2935256 follow-up by alexpott: Remove all usages of drupal_get_message and drupal_set_message in modules - PHP5.5 break

core/lib/Drupal/Core/Form/ConfigFormBase.php

@@ -3,7 +3,6 @@
 namespace Drupal\Core\Form;
 
 use Drupal\Core\Config\ConfigFactoryInterface;
-use Drupal\Core\Messenger\MessengerTrait;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
@@ -11,7 +10,6 @@
  */
 abstract class ConfigFormBase extends FormBase {
   use ConfigFormBaseTrait;
-  use MessengerTrait;
 
   /**
    * Constructs a \Drupal\system\ConfigFormBase object.