I somehow forgot to propagate roles into UnivCos. Very
simple fix, happily.

Test Plan: simplCore/should_compile/T11232

Reviewers: bgamari, austin, simonpj

Reviewed By: simonpj

Subscribers: simonpj, thomie

Differential Revision: https://phabricator.haskell.org/D1645

GHC Trac Issues: #11232