Merge branch 'MDL-62868-35' of https://github.com/snake/moodle into MOODLE_35_STABLE

Author: David Monllao

group/assign.php

@@ -59,13 +59,18 @@
         // Invalidate the course groups cache seeing as we've changed it.
         cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($courseid));
 
+        // Invalidate the user_group_groupings cache, too.
+        cache_helper::purge_by_definition('core', 'user_group_groupings');
     } else if (isset($frm->remove) and !empty($frm->removeselect)) {
         foreach ($frm->removeselect as $groupid) {
             // Ask this method not to purge the cache, we'll do it ourselves afterwards.
             groups_unassign_grouping($grouping->id, (int)$groupid, false);
         }
         // Invalidate the course groups cache seeing as we've changed it.
         cache_helper::invalidate_by_definition('core', 'groupdata', array(), array($courseid));
+
+        // Invalidate the user_group_groupings cache, too.
+        cache_helper::purge_by_definition('core', 'user_group_groupings');
     }
 }