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

vendor/symfony/dependency-injection/Compiler/LoggingFormatter.php

@@ -0,0 +1,45 @@
+<?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\DependencyInjection\Compiler;
+
+/**
+ * Used to format logging messages during the compilation.
+ *
+ * @author Johannes M. Schmitt <schmittjoh@gmail.com>
+ */
+class LoggingFormatter
+{
+    public function formatRemoveService(CompilerPassInterface $pass, $id, $reason)
+    {
+        return $this->format($pass, sprintf('Removed service "%s"; reason: %s', $id, $reason));
+    }
+
+    public function formatInlineService(CompilerPassInterface $pass, $id, $target)
+    {
+        return $this->format($pass, sprintf('Inlined service "%s" to "%s".', $id, $target));
+    }
+
+    public function formatUpdateReference(CompilerPassInterface $pass, $serviceId, $oldDestId, $newDestId)
+    {
+        return $this->format($pass, sprintf('Changed reference of service "%s" previously pointing to "%s" to "%s".', $serviceId, $oldDestId, $newDestId));
+    }
+
+    public function formatResolveInheritance(CompilerPassInterface $pass, $childId, $parentId)
+    {
+        return $this->format($pass, sprintf('Resolving inheritance for "%s" (parent: %s).', $childId, $parentId));
+    }
+
+    public function format(CompilerPassInterface $pass, $message)
+    {
+        return sprintf('%s: %s', get_class($pass), $message);
+    }
+}