add comment where one needs to use the origin_server_ts

Signed-off-by: Timo K <[email protected]>

Author: toger5

Diff for: src/matrixrtc/MatrixRTCSession.ts

@@ -625,6 +625,7 @@ export class MatrixRTCSession extends TypedEventEmitter<MatrixRTCSessionEvent, M
 
         if (prevMembership) m.created_ts = prevMembership.createdTs();
         if (m.created_ts) m.expires_ts = m.created_ts + (m.expires ?? 0);
+        // TODO: Date.now() should be the origin_server_ts (now).
         else m.expires_ts = Date.now() + (m.expires ?? 0);
 
         return m;