Add provd and last ubuntu desktop init

[sergio-costas]

This patch replaces the custom-modified ubuntu-core-desktop-init snap with the upstream ubuntu-desktop-init snap. It requires canonical/ubuntu-core-desktop#73

[sergio-costas]

The changes in ubuntu-desktop-provision have been included, so now the unneeded pages (ubuntu PRO, license and accessibility) aren't show.

[sergio-costas]

I don't know what happens now, but I can't launch Firefox. This is what is shown in journal:

SECCOMP auid=1000 uid=1000 gid=1000 ses=2 subj=snap.ubuntu-desktop-session.ubuntu-desktop-session pid=31880 comm="gnome-shell" exe="/usr/bin/gnome-shell" sig=0 arch=c000003e syscall=434 compat=0 ip=0x75bc8504b88d code=0x50000
AVC apparmor="DENIED" operation="file_mmap" class="file" profile="snap.ubuntu-desktop-session.ubuntu-desktop-session" name="/snap/snapd/22242/usr/lib/x86_64-linux-gnu/libpthread.so.0" pid=46784 comm="snap" requested_mask="m" denied_mask="m" fsuid=1000 ouid=0
/usr/bin/snap: error while loading shared libraries: libpthread.so.0: failed to map segment from shared object
kauditd_printk_skb: 17 callbacks suppressed
audit: type=1326 audit(1719403245.933:900): auid=1000 uid=1000 gid=1000 ses=2 subj=snap.ubuntu-desktop-session.ubuntu-desktop-session pid=31880 comm="gnome-shell" exe="/usr/bin/gnome-shell" sig=0 arch=c000003e syscall=434 compat=0 ip=0x75bc8504b88d code=0x50000
audit: type=1400 audit(1719403245.933:901): apparmor="DENIED" operation="file_mmap" class="file" profile="snap.ubuntu-desktop-session.ubuntu-desktop-session" name="/snap/snapd/22242/usr/lib/x86_64-linux-gnu/libpthread.so.0" pid=46784 comm="snap" requested_mask="m" denied_mask="m" fsuid=1000 ouid=0
apparmor="DENIED" operation="dbus_method_call"  bus="session" path="/org/freedesktop/systemd1" interface="org.freedesktop.systemd1.Manager" member="StartTransientUnit" mask="send" name="org.freedesktop.systemd1" pid=31880 label="snap.ubuntu-desktop-session.ubuntu-desktop-session" peer_pid=31612 peer_label="unconfined"
Could not create transient scope for PID 46784: GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: An AppArmor policy prevents this sender from sending this message to this recipient; type="method_call", sender=":1.19" (uid=1000 pid=31880 comm="/usr/bin/gnome-shell " label="snap.ubuntu-desktop-session.ubuntu-desktop-session (enforce)") interface="org.freedesktop.systemd1.Manager" member="StartTransientUnit" error name="(unset)" requested_reply="0" destination="org.freedesktop.systemd1" (uid=1000 pid=31612 comm="/lib/systemd/systemd --user " label="unconfined")

[sergio-costas]

@jhenstridge with the old snapd and the old core-base-desktop it does work... I'll try now with the new core-base-desktop and the old snapd.

[sergio-costas]

Confirmed: with the old snapd and the current, rebased code of core-base-desktop, it does work. So it seems a problem in snapd.

[jhenstridge]

If you get rid of the provd user in 000-provide-uids-gids.chroot (so we're just adding a provd group), I think this is fine to merge.

The auto-build recipe will publish to latest/candidate, so won't affect any existing users: we can do the remaining testing with a published package before promoting it to stable.

[sergio-costas]

@jhenstridge Removed.