MB-11661 Don't check the checkpoint manager upon ejecting an item

As a checkpoint has blob instances inside, we don't need to check
the checkpoint manager to see if we can eject an item from the
hash table.

Change-Id: I57fc887dc80b88ba275bc50ef7b7f8a5ff45e8c7
Reviewed-on: http://review.couchbase.org/39334
Reviewed-by: abhinav dangeti <abhinav@couchbase.com>
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Chiyoung Seo <chiyoung@couchbase.com>