Clutter.Color no longer exists.
(Also remove the adwaita shim, which is a left-over from previous
RHEL versions that did not include libadwaita)
Resolves: https://issues.redhat.com/browse/RHEL-51223
Re-apply rebased and updated version of the RHEL 9 downstream
patches, with some exceptions:
Branding is still TBD, so has been left out for now.
The desktop-icons extension will be replaced by an upstreamed
version of desktop-icons-ng, which is still work-in-progress.
Both dash-to-dock and dash-to-panel will be moved to separate
packages, based on the existing Fedora package.
It was decided to drop the panel-favorites and updates-dialog
extensions.
Resolves: RHEL-34255
