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

vendor/phpunit/php-code-coverage/src/CodeCoverage/Util/InvalidArgumentHelper.php

@@ -0,0 +1,39 @@
+<?php
+/*
+ * This file is part of the PHP_CodeCoverage package.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Factory for PHP_CodeCoverage_Exception objects that are used to describe
+ * invalid arguments passed to a function or method.
+ *
+ * @since Class available since Release 1.2.0
+ */
+class PHP_CodeCoverage_Util_InvalidArgumentHelper
+{
+    /**
+     * @param int    $argument
+     * @param string $type
+     * @param mixed  $value
+     */
+    public static function factory($argument, $type, $value = null)
+    {
+        $stack = debug_backtrace(false);
+
+        return new PHP_CodeCoverage_Exception(
+            sprintf(
+                'Argument #%d%sof %s::%s() must be a %s',
+                $argument,
+                $value !== null ? ' (' . gettype($value) . '#' . $value . ')' : ' (No Value) ',
+                $stack[1]['class'],
+                $stack[1]['function'],
+                $type
+            )
+        );
+    }
+}