indexer: persist initial build completion
indexer: persist initial build completion

During initial build in-memory snapshots are skipped.
So its necessary to create persistent snapshot at build
completion. otherwise the index moves to active state without any
snapshot.

Change-Id: Id19ca861f8b0835104409bc3cb6f2561a77c12a0

jchris/indexing,jchris/indexing,jchris/indexing,jchris/indexing