Correct comment.
Bug 958900 - Schedule a periodic sync for new FxAccountSyncAdapter.
Fuzz periodic syncs for backoff purposes.
Review comment: Bundle.EMPTY.
Refactor out BackoffHandler.
Extract SchedulePolicy out of FxAccountSyncAdapter.
Partially refactor BackoffHandler.shouldSync out of SyncAdapter.
Fleshing out backoff and scheduling in FxAccountSyncAdapter.