Comment 3 for bug 1567061

This seems quite straightforward. drupal8 will be a new source/binary package, so there is zero risk in including it now. I think we shoudl remove drupal7 from xenial then. If some users need it, we can reintroduce it into xenial-updates later on when there's a version that works with php7 again, but I wouldn't ship a known-broken version in release. There are no reverse dependencies to drupal7.