Comment 1 for bug 1302838

The only fix I can think of it to catch the AgentNotFoundByTypeHost and return an empty set of networks, since for requests like 'list_active_networks_on_active_dhcp_agent' is clear that the agent was not learnt by Neutron yet so throwing the exception doesn't make much sense.

If the goal of this bug was to find a way of making Neutron learn an agent quicker...well this requires some brainstorming :)