diff -u b/core/tests/bootstrap.php b/core/tests/bootstrap.php
--- b/core/tests/bootstrap.php
+++ b/core/tests/bootstrap.php
@@ -81,9 +81,6 @@
 $dirs = array_reduce($dirs, 'array_merge', array());
 drupal_phpunit_register_extension_dirs($loader, $dirs);
 
-// Look into removing these later.
-//define('REQUEST_TIME', (int) $_SERVER['REQUEST_TIME']);
-
 // Set sane locale settings, to ensure consistent string, dates, times and
 // numbers handling.
 // @see \Drupal\Core\DrupalKernel::bootEnvironment()