Fix dispatch of onRestoreFinished()

The agent instance wasn't properly being conveyed from the generic
restore engine implementation to the state machine handling the
lifecycles.  On top of that, the lifecycle wasn't advancing to the
restore-finished callback phase properly in the full-data restore
case.

Bug 22194736

Change-Id: Ic649d6a196adbd21a4a0f3083c7eed2fff383e52