- Patch #534594 by catch, Frando: add registry_rebuild() to update.php.

update.php

@@ -375,6 +375,10 @@ if (empty($op) && update_access_allowed()) {
   // Set up theme system for the maintenance page.
   drupal_maintenance_theme();
 
+  // Rebuild the registry to ensure that removed hooks in modules do not result
+  // in undefined function errors and that newly defined hooks are called.
+  registry_rebuild();
+
   // Check the update requirements for Drupal.
   update_check_requirements();