Update to drupal-org-drupal 8.0.0-rc2. For more information, see https://www.drupal.org/node/2598668

vendor/symfony/dependency-injection/Tests/Fixtures/containers/container8.php

@@ -1,14 +0,0 @@
-<?php
-
-use Symfony\Component\DependencyInjection\ContainerBuilder;
-use Symfony\Component\DependencyInjection\ParameterBag\ParameterBag;
-
-$container = new ContainerBuilder(new ParameterBag(array(
-    'FOO' => '%baz%',
-    'baz' => 'bar',
-    'bar' => 'foo is %%foo bar',
-    'escape' => '@escapeme',
-    'values' => array(true, false, null, 0, 1000.3, 'true', 'false', 'null'),
-)));
-
-return $container;