Replacing polkit JS backend

[Colin Walters]

Based on some (long ago now) in-person discussion with the previous polkit maintainer:
the JS backend was added for a reason from a real-world nontrivial in size desktop deployment.
That said I don't have contact with them myself and unfortunately the original commit
aeb2b50a7b0ed1411df81790231cd902d6e76e56
doesn't give us any hints.  I wouldn't be surprised if they don't use it anymore.

At a practical level I think we'd have to ship both (really all 3) things for a while
at least in Fedora; e.g.
https://goldmann.pl/blog/2012/12/03/configuring-polkit-in-fedora-18-to-access-virt-manager/
and
https://major.io/2015/04/11/run-virsh-and-access-libvirt-as-a-regular-user/
and variants are commonly used (I use that JS rule on this workstation too). 

Anyways, are you interested in being more active in upstream polkit?  There
are some outstanding patches to review;
https://bugs.freedesktop.org/show_bug.cgi?id=99741
for example.  From my perspective I'm fine adding you to the people with
push access.

Though it'd be great to have Miloslav weigh in on some of this too; particularly
things like @smcv's suggestion of a pkla translator as @mtrmac also maintains
<https://pagure.io/polkit-pkla-compat/>.