Fatal error: Uncaught Error: Class "Drupal\Core\PageCache\ChainRequestPolicy" not found in /home/www/drupal8/test/core/modules/dynamic_page_cache/src/PageCache/RequestPolicy/DefaultRequestPolicy.php:15 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/modules/dynamic_page_cache/src/PageCache/RequestPolicy/DefaultRequestPolicy.php on line 15