Comment 9 for bug 1424096

I faced the bug while reworking unit tests into functional tests: when performing steps described in the description I get:
 2015-12-15 17:41:23,484 ERROR [neutron.callbacks.manager] Error during notification for neutron.db.l3_dvrscheduler_db._notify_port_delete port, after_delete
    Traceback (most recent call last):
      File "neutron/callbacks/manager.py", line 141, in _notify_loop
        callback(resource, event, trigger, **kwargs)
      File "neutron/db/l3_dvrscheduler_db.py", line 485, in _notify_port_delete
        context, router['agent_id'], router['router_id'])
      File "neutron/db/l3_dvrscheduler_db.py", line 439, in remove_router_from_l3_agent
        router = self.get_router(context, router_id)
      File "neutron/db/l3_db.py", line 451, in get_router
        router = self._get_router(context, id)
      File "neutron/db/l3_db.py", line 137, in _get_router
        raise l3.RouterNotFound(router_id=router_id)
    RouterNotFound: Router 7d52836b-8fe5-4417-842f-3cbe0920c89c could not be found

and router is not removed from host which has no more dvr serviceable ports.

Looks like we also need admin context in order to remove admin router from a host when non-admin tenant removes last dvr serviceable port on a shared network.