Fix intermittent race condition in SyncCalendarTests

Fixes this problem, which (presumably) happens when the test starts before
the calendar has been synced:

junit.framework.AssertionFailedError: Daily recurring event should have been deleted. expected:< 1 > but was:< 319 >
at com.android.providers.calendar.SyncCalendarTest.testCreateAndDeleteNewRecurringEvent(SyncCalendarTest.java:54)
[...]
1 file changed