Add a TODO about a possible use after free bug.

src/servers/notification/AppGroupView.cpp

@@ -238,6 +238,9 @@ AppGroupView::AddInfo(NotificationView* view)
 
 		for (int32 i = 0; i < children; i++) {
 			if (id == fInfo[i]->MessageID()) {
+				// TODO: because NotificationWindow also tracks these
+				// views, we may be heading towards a use-after-free with
+				// this code.
 				GetLayout()->RemoveView(fInfo[i]);
 				delete fInfo[i];