Comment 4 for bug 1746483

It looks like this was likely regressed in Mitaka with this change:

https://review.openstack.org/#/c/202678/

Because before that change, the logic could handle no image being supplied with the server create request:

        spec = filter_properties.get('request_spec', {})
        props = spec.get('instance_properties', {})
        image_ref = props.get('image_ref')
        image_isolated = image_ref in isolated_images

But then it was changed to this which breaks in this scenario:

        image_ref = spec_obj.image.id if spec_obj.image else None

I'm not sure what's in spec_obj.image though if it's not None or empty.