commit 4600618237254406bf078b7920ae180b672b7354
Author: Joel Pittet <joel@pittet.ca>
Date:   Tue Nov 18 07:04:19 2014 -0800

    fix

diff --git a/core/lib/Drupal/Core/EventSubscriber/DefaultExceptionSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/DefaultExceptionSubscriber.php
index 1aac625..c8bc8b1 100644
--- a/core/lib/Drupal/Core/EventSubscriber/DefaultExceptionSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/DefaultExceptionSubscriber.php
@@ -133,7 +133,7 @@ protected function onHtml(GetResponseForExceptionEvent $event) {
     }
 
     $content = $this->t('The website has encountered an error. Please try again later.');
-    $output = $this->bareHtmlPageRenderer->renderBarePage($content, ['#markup' => $this->t('Error')], 'maintenance_page');
+    $output = $this->bareHtmlPageRenderer->renderBarePage(['#markup' => $content], $this->t('Error'), 'maintenance_page');
     $response = new Response($output);
 
     if ($exception instanceof HttpExceptionInterface) {