Revert "Force base ref to www.php.net, and set it only once".

This is now fixed in the CDN configuration, so we can restore the old
behaviour.

This reverts commit f882125.

Author: derickr

include/header.inc

@@ -61,7 +61,9 @@ if (!isset($config["languages"])) {
   <meta charset="utf-8">
   <meta name="viewport" content="width=device-width, initial-scale=1.0">
 
-  <base href="https://www.php.net">
+  <?php if (!empty($_SERVER["BASE_HREF"])): ?>
+   <base href="<?php echo $_SERVER["BASE_HREF"]; ?>">
+  <?php endif ?>
 
   <title><?php echo $title ?></title>
 
@@ -103,6 +105,10 @@ if (!isset($config["languages"])) {
 <script type="text/javascript" src="/cached.php?t=<?php echo $modified?>&amp;f=<?php echo $filename?>"></script>
 <?php endforeach ?>
 
+<?php if (!empty($_SERVER["BASE_HREF"])): ?>
+ <base href="<?php echo $_SERVER["BASE_HREF"] ?>">
+<?php endif ?>
+
 <?php if (isset($config['meta_tags'])) { echo $config['meta_tags']; } ?>
 
 <?php if (is_primary_site()) { ?>