Make sure an attendee's version of a cancelled instance is the last variant they saw.


git-svn-id: https://svn.calendarserver.org/repository/calendarserver@13700 e27351fd-9f3e-4f54-a53b-843176b1656c
Make sure an attendee's version of a cancelled instance is the last variant they saw.


git-svn-id: https://svn.calendarserver.org/repository/calendarserver@13701 e27351fd-9f3e-4f54-a53b-843176b1656c