Fixes #229 use correct base class for 3.2

classes/search/activity.php

@@ -33,5 +33,5 @@ defined('MOODLE_INTERNAL') || die();
  * @copyright  2016 Dan Marsden
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-class activity extends \core_search\area\base_activity {
+class activity extends \core_search\base_activity {
 }