Comment 10 for bug 1732703

Further extensive discussion at https://irclogs.ubuntu.com/2017/12/13/%23ubuntu-devel.html#t15:15

Our current belief is that the bug is in the systemd package, introduced by the SRU tracked in bug 1656280. That update broke our standard test for determining if we're on a systemd system by creating /run/systemd/system when the systemd package is installed even if pid 1 is upstart.

It looks like this regressed eleven months ago but was only reported last month, so I don't think the MAAS fix is critical. I would prefer to get this fixed properly in systemd because it may have a wider impact than just MAAS.