$ git clone -n https://src.fedoraproject.org/rpms/webkitgtk.git /var/lib/mock/f40-build-787317-134744/root/chroot_tmpdir/scmroot/webkitgtk
Cloning into '/var/lib/mock/f40-build-787317-134744/root/chroot_tmpdir/scmroot/webkitgtk'...
$ git fetch origin 92dbb98196e0e9e50c21e367a500701df9c1a917:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/webkitgtk
 * [new ref]         92dbb98196e0e9e50c21e367a500701df9c1a917 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 92dbb98 Remove use of real-time scheduling on vblank thread