Future of xdg-shell v5 support in weston

[Derek Foreman]

Hello,

As you all may know, xdg-shell v5 and xdg-shell stable can't currently 
co-exist in the same compositor, as both define structures with the same 
name (such as struct xdg_surface_interface).

A solid effort was made to add functionality to wayland-scanner to 
resolve this, but turned out to be a Very Hard Problem:
https://lists.freedesktop.org/archives/wayland-devel/2018-January/036549.html

Is a good summary of where that patch series currently sits.

That leaves us with a bit of a problem - weston currently support 
xdg-shell v5, and that's blocking any chance of adopting xdg-shell final.

It's my opinion that supporting xdg-shell final is rather important for 
the wayland reference compositor.

So, I think we need to consider removing xdg-shell v5 from weston and 
its included clients as soon as is reasonable.

It should probably be considered deprecated since the introduction of 
xdg-shell v6 into wayland-protocols in late 2015.  I'm sure there are 
still users out there, but it has always been labeled "unstable" with a 
firm promise that it would disappear eventually.

Do we have any opinions on when we can strip this out?  I think keeping 
it for the next release and removing it immediately after is pragmatic 
(with a firm warning in the release notes that this is coming).

Myself, I'd be happy to start drafting patches to remove it immediately 
- weston isn't intended to be anyone's desktop, so I don't think 
arguments that some released software will fail to run on weston should 
be given substantial weight...

Also, I don't think toytoolkit clients failing to connect to a 
compositor that only has v5 support is a major concern either.

Thanks,
Derek