Allow dEQP to reset this particular state variable, while still throwing an UNIMPLEMENTED error if we try to render with primitive restart enabled. BUG=angle:901 Change-Id: I1ab46ff4d8bff2775225b083f08d156b9422b9c5 Reviewed-on: https://chromium-review.googlesource.com/244840Reviewed-by: Geoff Lang <geofflang@chromium.org> Reviewed-by: Zhenyao Mo <zmo@chromium.org> Tested-by: Jamie Madill <jmadill@chromium.org>
