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

vendor/symfony/dependency-injection/Tests/Fixtures/containers/container21.php

@@ -0,0 +1,20 @@
+<?php
+
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Definition;
+
+$container = new ContainerBuilder();
+
+$bar = new Definition('Bar');
+$bar->setConfigurator(array(new Definition('Baz'), 'configureBar'));
+
+$fooFactory = new Definition('FooFactory');
+$fooFactory->setFactory(array(new Definition('Foobar'), 'createFooFactory'));
+
+$container
+    ->register('foo', 'Foo')
+    ->setFactory(array($fooFactory, 'createFoo'))
+    ->setConfigurator(array($bar, 'configureFoo'))
+;
+
+return $container;