Reproducer:
This policy chain https://github.com/3scale/APIcast/blob/master/t/apicast-policy-on_failed.t#L77 does not work in conditional policy because conditional policy doesn't use add_policy function https://github.com/3scale/APIcast/blob/master/gateway/src/apicast/policy_chain.lua#L17 like ordinary policy chain does. On failed policy sets policy_error_callback which needs to be called if there is any issue during loading the policy.