Add one more test for SPL autoload defaults.

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>

tests/HTMLPurifier/PHPT/loading/auto-with-spl-autoload-default.phpt

@@ -0,0 +1,25 @@
+--TEST--
+HTMLPurifier.auto.php using spl_autoload_register default
+--SKIPIF--
+<?php
+if (!function_exists('spl_autoload_register')) {
+    echo "skip - spl_autoload_register() not available";
+}
+--FILE--
+<?php
+spl_autoload_extensions(".php");
+spl_autoload_register();
+
+require '../library/HTMLPurifier.auto.php';
+require 'HTMLPurifier/PHPT/loading/_autoload.inc';
+$config = HTMLPurifier_Config::createDefault();
+$purifier = new HTMLPurifier($config);
+echo $purifier->purify('<b>Salsa!') . "
+";
+
+// purposely invoke standard autoload
+$test = new default_load();
+
+--EXPECT--
+<b>Salsa!</b>
+Default loaded

tests/default_load.php

@@ -0,0 +1,3 @@
+<?php
+class default_load { }
+echo "Default loaded\n";