[ticket/217] Silence errors in tests, not code.

Use a mock user object for testing bbcode.

PHPBB3-217

tests/mock_user.php

@@ -0,0 +1,20 @@
+<?php
+/**
+*
+* @package testing
+* @copyright (c) 2011 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
+*
+*/
+
+/**
+* Mock user class.
+* This class is used when tests invoke phpBB code expecting to have a global
+* user object, to avoid instantiating the actual user object.
+* It has a minimum amount of functionality, just to make tests work.
+*/
+class phpbb_mock_user
+{
+	public $host = "testhost";
+	public $page = array('root_script_path' => '/');
+}