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

vendor/symfony/http-kernel/DependencyInjection/AddClassesToCachePass.php

@@ -0,0 +1,46 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\HttpKernel\DependencyInjection;
+
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
+use Symfony\Component\HttpKernel\Kernel;
+
+/**
+ * Sets the classes to compile in the cache for the container.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class AddClassesToCachePass implements CompilerPassInterface
+{
+    private $kernel;
+
+    public function __construct(Kernel $kernel)
+    {
+        $this->kernel = $kernel;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function process(ContainerBuilder $container)
+    {
+        $classes = array();
+        foreach ($container->getExtensions() as $extension) {
+            if ($extension instanceof Extension) {
+                $classes = array_merge($classes, $extension->getClassesToCompile());
+            }
+        }
+
+        $this->kernel->setClassCache(array_unique($container->getParameterBag()->resolveValue($classes)));
+    }
+}