MB-21690 Fix stat names used to get drift thresholds.
MB-21690 Fix stat names used to get drift thresholds.

Change-Id: Ib79e2781b6ef158d89923994cd55adb37d2d9557
Reviewed-on: http://review.couchbase.org/70008
Tested-by: Aliaksey Artamonau <3c875bcfb3adf2a65b2ae7686ca921e6c9433147@gmail.com>
Reviewed-by: Dave Finlay <7b10a9ed9f70e64c30b07607a671ae61c33f14c8@couchbase.com>

ceejatec/ns_server,membase/ns_server,membase/ns_server,membase/ns_server,membase/ns_server,ceejatec/ns_server,membase/ns_server,membase/ns_server,ceejatec/ns_server,ceejatec/ns_server,ceejatec/ns_server,ceejatec/ns_server