criterion update: add "switch user" to Shutdown, reboot, logout

[Kamil Paral]

> Matthias Clasen wrote:
> I think user switching is much less important than the other things on
> your list (login, shutdown, reboot) 

I agree it's not as important as shutdown, but the question is whether it's important enough to be considered "basic functionality" and we block the release when it's broken heavily.

For example, by our current standards, gnome-calculator must work or we do not ship:
https://fedoraproject.org/wiki/Fedora_22_Final_Release_Criteria#Default_application_functionality
We also don't ship when we don't have high-contrast icons for all apps, or when we miss some artwork.

All of that is probably not as important as shutdown working, but still forms some kind of basis which needs to work.

Btw, I just realized that it could be argued that user switching is already covered by this criterion:
https://fedoraproject.org/wiki/Fedora_22_Final_Release_Criteria#Default_panel_functionality
but it's good we're having this discussion, at least we can clarify this.

> if user switching is broken, the
> majority of our users won't even notice because they are on single-user
> systems.

It's hard to make some estimates here, but judging by my surroundings, single user systems are very common for us IT geeks, but do not necessarily represent Fedora's larger audience. On my home laptop, I have user profiles for me and for my girlfriend (my account is mostly logged in when the laptop gets suspended), and I need her to be able to use it even when I'm not around to manually switch VTs. My dad's laptop has user profiles for him and my mom. And even I have a guest account on my work laptop when I need to lend it to someone for a minute, I guess that's also a very common use case.

It seems to me that family usage is the most commonly mentioned scenario when I see people complaining about this feature being broken.

> 
> Testing it is fine of course, but I don't really think we should block
> on this. 

Do you mean not block on it even for Final, i.e. at all, or Beta?

What I see as a problem is that any serious bugs [1] cut off multi-user usage of that system almost completely. I feel that we're losing a really big part of our audience this way. And now that we have Fedora Workstation product (and the KDE spin) with its more targeted focus on a specific user base, it would be a real pity to sacrifice those people.


> Also worth considering: user switching has never worked 100%
> reliably, so increased qa focus may just uncover old heisenbugs, and
> turn them into blocking issues.

It that a bad thing or a good thing? Could this be a worthy goal for F22? It's still pretty early in the cycle. 
Or if you think it's too late, does it make sense to target this for F23? Is it about technical complexity, or is there no will/manpower to maintain this? (Since this is one of my painful issues with GNOME, I can promise you some QA time from my side:)).

Thanks,
Kamil

[1] https://bugzilla.gnome.org/show_bug.cgi?id=719418