MB-21142: Ensure vbucket states are persisted before the test
MB-21142: Ensure vbucket states are persisted before the test

In test_tap_filter_stream, vb ids 0 to 3 are set to active
before the test. The test needs to ensure that all the vbucket
states are persisted and the respective couchstore files created
so that there is no race between file creation and operations
on the file

Context: test_tap_filter_stream

Change-Id: Idad34474bdf418504012731459cf4eb3272b1ba9
Reviewed-on: http://review.couchbase.org/68264
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Dave Rigby <a09264da4832c7ff1d3bf1608a19f4b870f93750@couchbase.com>

daverigby/ep-engine,membase/ep-engine,daverigby/kv_engine,membase/ep-engine,daverigby/kv_engine,couchbase/ep-engine,couchbase/ep-engine,daverigby/ep-engine,daverigby/ep-engine,membase/ep-engine,couchbase/ep-engine,daverigby/kv_engine,daverigby/ep-engine,membase/ep-engine,couchbase/ep-engine,daverigby/kv_engine