CBQE-0 :: fix verificationf for unacked bytes in upr

Change-Id: Ib751d2a0f1239a36969a14bde6abcce37cd914d0
Reviewed-on: http://review.couchbase.org/38110
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Reviewed-by: Thuan Nguyen <soccon@gmail.com>
Reviewed-by: Parag Agarwal <agarwal.parag@gmail.com>
Tested-by: Parag Agarwal <agarwal.parag@gmail.com>