CBQE-0:: fix failover test case failures
- name change of withOps to withMutationOps
- unwanted duplicated verification removed for unacked bytes

Change-Id: I7417b2c1c702029ed03f0104918f099a3e0ad364
Reviewed-on: http://review.couchbase.org/39671
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Parag Agarwal <agarwal.parag@gmail.com>
Tested-by: Parag Agarwal <agarwal.parag@gmail.com>