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

vendor/symfony/http-kernel/Tests/Fixtures/ExtensionPresentBundle/Command/BarCommand.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace Symfony\Component\HttpKernel\Tests\Fixtures\ExtensionPresentBundle\Command;
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\HttpKernel\Bundle;
+
+/**
+ * This command has a required parameter on the constructor and will be ignored by the default Bundle implementation.
+ *
+ * @see Bundle::registerCommands()
+ */
+class BarCommand extends Command
+{
+    public function __construct($example, $name = 'bar')
+    {
+    }
+}