Comment 1 for bug 1280357

As discussed on several proposed patches around this (see https://review.openstack.org/#/c/80619/ or https://review.openstack.org/#/c/80619/ which actually rejects this solution).

I will move this bug to "won't fix", and will raise a BP targeted for Juno to use some of the code added in https://blueprints.launchpad.net/nova/+spec/admin-event-callback-api to make interactions between nova and cinder better and avoid the need for a configurable timeout.