Notify clients when devices are deleted (#1233)

* Recheck device lists when join/leave events come in

* Add PerformDeviceDeletion

* Notify clients when devices are deleted

* Unbreak things

* Remove debug logging

syncapi/consumers/roomserver.go

@@ -35,6 +35,7 @@ type OutputRoomEventConsumer struct {
 	rsConsumer *internal.ContinualConsumer
 	db         storage.Database
 	notifier   *sync.Notifier
+	keyChanges *OutputKeyChangeEventConsumer
 }
 
 // NewOutputRoomEventConsumer creates a new OutputRoomEventConsumer. Call Start() to begin consuming from room servers.
@@ -44,6 +45,7 @@ func NewOutputRoomEventConsumer(
 	n *sync.Notifier,
 	store storage.Database,
 	rsAPI api.RoomserverInternalAPI,
+	keyChanges *OutputKeyChangeEventConsumer,
 ) *OutputRoomEventConsumer {
 
 	consumer := internal.ContinualConsumer{
@@ -56,6 +58,7 @@ func NewOutputRoomEventConsumer(
 		db:         store,
 		notifier:   n,
 		rsAPI:      rsAPI,
+		keyChanges: keyChanges,
 	}
 	consumer.ProcessMessage = s.onMessage
 
@@ -160,9 +163,29 @@ func (s *OutputRoomEventConsumer) onNewRoomEvent(
 	}
 	s.notifier.OnNewEvent(&ev, "", nil, types.NewStreamToken(pduPos, 0, nil))
 
+	s.notifyKeyChanges(&ev)
+
 	return nil
 }
 
+func (s *OutputRoomEventConsumer) notifyKeyChanges(ev *gomatrixserverlib.HeaderedEvent) {
+	if ev.Type() != gomatrixserverlib.MRoomMember || ev.StateKey() == nil {
+		return
+	}
+	membership, err := ev.Membership()
+	if err != nil {
+		return
+	}
+	switch membership {
+	case gomatrixserverlib.Join:
+		s.keyChanges.OnJoinEvent(ev)
+	case gomatrixserverlib.Ban:
+		fallthrough
+	case gomatrixserverlib.Leave:
+		s.keyChanges.OnLeaveEvent(ev)
+	}
+}
+
 func (s *OutputRoomEventConsumer) onNewInviteEvent(
 	ctx context.Context, msg api.OutputNewInviteEvent,
 ) error {