CBQE:2380 Add tests for new dev item MB-10179 to handle replication in idle-xdcr scenarios

Change-Id: I7997c1b8fed94d16d52f43541da9d764efe82d76
Reviewed-on: http://review.couchbase.org/40580
Tested-by: Aruna Piravi <aruna@couchbase.com>
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>