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

vendor/symfony/css-selector/XPath/Extension/AbstractExtension.php

@@ -0,0 +1,63 @@
+<?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\CssSelector\XPath\Extension;
+
+/**
+ * XPath expression translator abstract extension.
+ *
+ * This component is a port of the Python cssselect library,
+ * which is copyright Ian Bicking, @see https://github.com/SimonSapin/cssselect.
+ *
+ * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ */
+abstract class AbstractExtension implements ExtensionInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function getNodeTranslators()
+    {
+        return array();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getCombinationTranslators()
+    {
+        return array();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getFunctionTranslators()
+    {
+        return array();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPseudoClassTranslators()
+    {
+        return array();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getAttributeMatchingTranslators()
+    {
+        return array();
+    }
+}