MB-5662 Don't skip updating vb_state in couchKVStore.
MB-5662 Don't skip updating vb_state in couchKVStore.

As vbucket state consists of vb_state, checkpoint_id, and other
fields and we remove duplicate vb snapshot tasks, we should not
skip updating vb_state in couchKVStore.

Change-Id: Id40089af5d5987784e15080e40ebbd4563878cd7
Reviewed-on: http://review.couchbase.org/17580
Reviewed-by: Jin Lim <c45cd80a556f432a3607171a6818cd5a074b5cd4@couchbase.com>
Tested-by: Chiyoung Seo <8b279095f11c26cc21045fda5a3e51debb005aa9@gmail.com>

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