Default App: GNOME Logs

[Jeremy Bicha]

gnome-logs is a simple frontend to the systemd journal. For years, we
have shipped gnome-system-log.

The MIR for gnome-logs is actually already approved [1]. We just need
to decide if we want it. I propose we drop gnome-system-log and ship
gnome-logs instead in the default Ubuntu desktop.

gnome-system-log
---------------------------
- Last release was 4 years ago: 3.9.90
+ Default logs shown are auth.log, dpkg.log, mail.log, syslog, and Xorg.0.log
- Shows a warning on startup in a default install because there is no
mail.log by default
- Cannot show any systemd logs. Users would need to just run
journalctl or install gnome-logs to see those logs.

gnome-logs
----------------
+ Last release was this month
+ Core GNOME app since 3.20
+ Shows the auth, syslog and Xorg logs (I believe those logs are
actually originally from the systemd journal and there are just output
to disk for the benefit of people who don't want to use the systemd
journal).
- Only shows systemd logs so it can't currently show logs for things
like dpkg, apt, apport or lightdm
- systemd journal is not persistent by default. This means that only
the current boot is shown. Some important logs that can only be seen
at shutdown or a failed start won't be seen. [2]
- scrolling is a bit unusual in gnome-logs as can be seen in the All tab.

I believe by default, gnome-logs shows a lot more logs than
gnome-system-log does especially if we enabled the persistent journal.

Note: There is a scrolling performance bug in gnome-logs that has
recently been fixed in artful and is in unapproved queue for zesty.
[3]

Note: A GSOC contributor has made several improvements to gnome-logs.
[4] The Shell search provider isn't merged yet but you can try out the
rest of the UI changes in the GNOME3 Staging PPA for artful.

[1] https://launchpad.net/bugs/1522078
[2] https://launchpad.net/bugs/1618188
[3] https://launchpad.net/bugs/1707554
[4] https://pranavganorkar.wordpress.com/2017/07/16/gnome-logs-july-gsoc-progress-report/

Thanks,
Jeremy Bicha