Fix bug where calendar-query report wityh recurrence expansion on a floating event would cause a 500 error.
Fix bug where calendar-query report wityh recurrence expansion on a floating event would cause a 500 error.

git-svn-id: 0c33e958600270102f91bf5868e396345dde476c@1508 e27351fd-9f3e-4f54-a53b-843176b1656c

red-hood/calendarserver,red-hood/calendarserver,red-hood/calendarserver,red-hood/calendarserver,red-hood/calendarserver,red-hood/calendarserver