Update severity is not decoded from the Package signal's info field

[foresto]

Since b30ab47408a4, PackageKit has been embedding a severity code into the Package signal's info field. That change included updates to packagekit-glib2 that decode the two original values now embedded in that field, but it looks like PackageKit-Qt never got a corresponding update. Consequently, Qt clients expecting to find certain values in that field no longer work correctly.

For example, KDE Discover uses that field to distinguish security updates from normal updates. It can no longer do so, because it checks for an InfoSecurity value, but PackageKit sends (InfoSecurity << 16 | InfoSecurity) instead. Security updates are therefore no longer getting priority or special indicators to alert the user to their importance.

Shouldn't PackageKit-Qt be updated, for parity with packagekit-glib2 and to keep clients from remaining broken?

[aleixpol]

Yes, it seems like PackageKit-Qt needs to be adapted.

[ximion]

How annoying, this API break shouldn't have happened this way :-/

[ximion]

This change in PackageKit was absolutely terrible - there already was a way to convey severity, we now have it duplicated to serve the DNF API for some reason, and we can now put packages in states like "unavailable" and "critical bugfix" at the same time.

I generally like it that there is a separate property for update severities now, and the info enum is way too overloaded anyway, but this is a bit of a terrible change.
Absolutely no backend is using it too, except for the DNF one - so only on Fedora & Co you won't get security updates highlighted, because it wasn't using the PackageKit backend API properly before, and instead of fixing that, it added a new field to PK's API, breaking it in the process...

Now the damage is done, even partially reverting this change will be a bit of a challenge, since this touched library API as well... I have ideas for that though. Offending PR, for future reference: PackageKit/PackageKit#475 - annoying that I didn't catch that back then to join the conversation :-/

I added some band-aid that hopefully does the trick for QPK in a way that doesn't break everything.

[foresto]

Related: PackageKit/PackageKit@b30ab47