Comment 0 for bug 1663505

devstack-gate downloads master branch if specified stable branch doesn't exist in project [0].
As result each time when new stable branch is specified in devstack-gate [1]. All projects that do not cut this branch start perform testing from master ---> master.

[0] https://github.com/openstack-infra/devstack-gate/blob/master/functions.sh#L502-L506
[1] https://github.com/openstack-infra/devstack-gate/commit/9c752b02fbd57c7021a7c9295bf4d68a0d1973a8