Update to drupal 8.0.0-rc1. For more information, see https://www.drupal.org/node/2582663

vendor/symfony/dependency-injection/Tests/Fixtures/containers/container10.php

@@ -0,0 +1,14 @@
+<?php
+
+require_once __DIR__.'/../includes/classes.php';
+
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Reference;
+
+$container = new ContainerBuilder();
+$container->
+    register('foo', 'FooClass')->
+    addArgument(new Reference('bar'))
+;
+
+return $container;