Clear cached CalendarObservers after Calendar wipe

* This fix may resolve the bugs referenced below; the issue fixed
  could cause pandemonium after the server commands a wipe of calendar
  data and most likely explains these issues (via Occam's Razor)

Bug: 4077499
Bug: 4064237
Change-Id: I628fb14ea2c04150d4f27341751f0eab61ee33d1
2 files changed