am 9b168fae: b/2167301 Guests were dropped when creating an exception to a recurring event.

Merge commit '9b168fae95ff394c3116bfdf61af3ccb2c4c3e34' into eclair-mr2

* commit '9b168fae95ff394c3116bfdf61af3ccb2c4c3e34':
  b/2167301 Guests were dropped when creating an exception to a recurring event.