When two routers are created at the same time, we can't assume the
status of each one. Instead of this, the status of each router is
first checked and then compared to the other router status.
Conflicts:
neutron/tests/functional/agent/l3/test_dvr_router.py
Change-Id: If20a3a414986ea29fbfd50616761c14e5b249b2c
Closes-Bug: #1819160
(cherry picked from commit 8f35331c91)
(cherry picked from commit 8ba5899942)