MB-9950 Wait for VB state snapshot before starting each unit test
MB-9950 Wait for VB state snapshot before starting each unit test

This will make sure that all the storage files are created before
receiving the traffic.

Change-Id: I2f10e65928df56913b2b600a4d6c65fc89c5ab1d
Reviewed-on: http://review.couchbase.org/33158
Reviewed-by: Michael Wiederhold <a17fed27eaa842282862ff7c1b9c8395a26ac320@couchbase.com>
Tested-by: Chiyoung Seo <fcffc23db27b19ee4ebba46695ee6b50e09216a2@couchbase.com>

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