diff -u b/core/modules/system/src/Tests/Theme/MessageTest.php b/core/modules/system/src/Tests/Theme/MessageTest.php
--- b/core/modules/system/src/Tests/Theme/MessageTest.php
+++ b/core/modules/system/src/Tests/Theme/MessageTest.php
@@ -15,7 +15,6 @@
  * @group Theme
  */
 class MessageTest extends KernelTestBase {
-
   /**
    * {@inheritdoc}
    */
@@ -28,7 +27,7 @@
     // Enable the Classy theme.
     \Drupal::service('theme_handler')->install(['classy']);
     $this->config('system.theme')->set('default', 'classy')->save();
-    
+
     drupal_set_message('An error occurred', 'error');
     drupal_set_message('But then something nice happened');
     $messages = array(
diff -u b/core/modules/system/templates/status-messages.html.twig b/core/modules/system/templates/status-messages.html.twig
--- b/core/modules/system/templates/status-messages.html.twig
+++ b/core/modules/system/templates/status-messages.html.twig
@@ -26,7 +26,6 @@
  */
 #}
 {% for type, messages in message_list %}
-
   <div class="{{ attributes.class }}" role="contentinfo" aria-label="{{ status_headings[type] }}">
     {% if type == 'error' %}
       <div role="alert">