This updates the index subscriber catchup function to update
subscriptions directly with notification instead of going through the
Run lifecycle process which avoids a case of receiving out of sync
index notifications while catch up is in progress.
Multiple typos in error type tests and review issues have also been
fixed in this commit.
This removes last set of references to IndexManager and integrates the
IndexSubscriber into the chain. All indexes have now been updated to
subscribe to the index subscriber for updates.
