Fatal error: Uncaught Error: Class "Symfony\Component\HttpKernel\Controller\ControllerResolver" not found in /home/www/drupal8/test/core/lib/Drupal/Core/Controller/ControllerResolver.php:28 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/lib/Drupal/Core/Controller/ControllerResolver.php on line 28