D3D: minor cleanup of gl::RangeUI usage. Bug: angleproject:7121 Change-Id: I444f1e5e96dab84315afc290d6044d0dee560d6e Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3651055 Commit-Queue: Stephen White <senorblanco@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>