- Re-enable and rebase gnome-packagekit-displaysize.patch.

- Rebased bnc-946886-install-signatures-in-viewer.patch.

- Update to version 3.21.91:
+ Re-instate the gpk-application app-menu (bgo#769931).
+ Don't use the deprecated GNOME_COMPILE_WARNINGS.
+ Remove duplicate prototypes for _get_type().
+ Ensure gpk-application gets the warning flags set.
+ Updated translations.

- Update to version 3.21.90:
+ Use new-style application IDs for flatpak.
+ Remove the broken markdown parsing module.
+ Updated translations.

- Update to version 3.21.4:
+ Depend on a non-obsolete PackageKit version.
+ Remove some unused API.
+ Remove unused animations.
+ Remove unused functionality.
+ Use new-style application IDs for flatpak.
+ Updated translations.
- Replace PackageKit-devel BuildRequires with
pkgconfig(packagekit-glib2), matching what configure looks for.
- Rebase patches:
+ gnome-packagekit-OnlyShowIn.patch
+ bnc#881245-update-test-affects-package-manager-should-restart-gpk-update-viewer.patch
+ bnc#939278-gnome-packagekit-asks-for-reboot-password-too-early.patch
- Disabled bnc-946886-install-signatures-in-viewer.patch: patch