Processes log message from a given hunt-induced flow.

def ProcessHuntFlowLog(flow_obj, log_msg):
  """Processes log message from a given hunt-induced flow."""

  if not hunt.IsLegacyHunt(flow_obj.parent_hunt_id):
    return

  hunt_urn = rdfvalue.RDFURN("hunts").Add(flow_obj.parent_hunt_id)
  flow_urn = hunt_urn.Add(flow_obj.flow_id)
  log_entry = rdf_flows.FlowLog(
      client_id=flow_obj.client_id,
      urn=flow_urn,
      flow_name=flow_obj.flow_class_name,
      log_message=log_msg)
  with data_store.DB.GetMutationPool() as pool:
    grr_collections.LogCollection.StaticAdd(
        hunt_urn.Add("Logs"), log_entry, mutation_pool=pool)