We are doing a desktop rebase in RHEL 7.6. The polkit version in RHEL is rather old and doesn't ship gettext .its files that are needed by other components (e.g. gnome-settings-daemon) to build. Please backport https://src.fedoraproject.org/rpms/polkit/c/fa6fd575804de92886c95d3bc2b7eb2abcd13760?branch=master I'm happy to help with the builds (got this already backported in https://copr.devel.redhat.com/coprs/klember/rhel-7-gnome-3-28/)
Thanks Jan!
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2018:3141