MB-5427: Fixed stats key unit test errors
MB-5427: Fixed stats key unit test errors

Change-Id: Idb5cfb3308f7379bdd3b38bd316d37725b503bb6
Reviewed-on: http://review.couchbase.org/16683
Reviewed-by: Chiyoung Seo <8b279095f11c26cc21045fda5a3e51debb005aa9@gmail.com>
Tested-by: Chiyoung Seo <8b279095f11c26cc21045fda5a3e51debb005aa9@gmail.com>

couchbase/ep-engine,teligent-ru/ep-engine,daverigby/kv_engine,sriganes/ep-engine,membase/ep-engine,abhinavdangeti/ep-engine,owendCB/ep-engine,daverigby/kv_engine,jimwwalker/ep-engine,sriganes/ep-engine,jimwwalker/ep-engine,abhinavdangeti/ep-engine,sriganes/ep-engine,owendCB/ep-engine,couchbase/ep-engine,hisundar/ep-engine,hisundar/ep-engine,membase/ep-engine,sriganes/ep-engine,abhinavdangeti/ep-engine,owendCB/ep-engine,hisundar/ep-engine,daverigby/ep-engine,abhinavdangeti/ep-engine,jimwwalker/ep-engine,daverigby/ep-engine,teligent-ru/ep-engine,membase/ep-engine,couchbase/ep-engine,daverigby/kv_engine,teligent-ru/ep-engine,hisundar/ep-engine,membase/ep-engine,daverigby/ep-engine,jimwwalker/ep-engine,daverigby/ep-engine,daverigby/kv_engine,owendCB/ep-engine,couchbase/ep-engine,abhinavdangeti/ep-engine,teligent-ru/ep-engine