MDL-21009 Group selector must use absolute links in order to work with javascript off

mod/data/view.php

@@ -296,7 +296,7 @@
     }
 
 /// Check to see if groups are being used here
-    $returnurl = 'view.php?d='.$data->id.'&search='.s($search).'&sort='.s($sort).'&order='.s($order).'&';
+    $returnurl = $CFG->wwwroot . '/mod/data/view.php?d='.$data->id.'&search='.s($search).'&sort='.s($sort).'&order='.s($order).'&';
     groups_print_activity_menu($cm, $returnurl);
     $currentgroup = groups_get_activity_group($cm);
     $groupmode = groups_get_activity_groupmode($cm);