MDL-35385 mod_chat: made sure no message popups display within the chat window

mod/chat/gui_basic/index.php

@@ -44,7 +44,7 @@ $context = get_context_instance(CONTEXT_MODULE, $cm->id);
 require_login($course, false, $cm);
 require_capability('mod/chat:chat', $context);
 $PAGE->set_pagelayout('base');
-$PAGE->set_popup_notification_allowed(false); // No popup notifications in the chat window
+$PAGE->set_popup_notification_allowed(false);
 
 /// Check to see if groups are being used here
  if ($groupmode = groups_get_activity_groupmode($cm)) {   // Groups are being used