This change enables the following tests:
dEQP-GLES2.functional.rasterization.culling.* 18/18
dEQP-GLES2.functional.rasterization.interpolation.* 12/12
dEQP-GLES2.functional.rasterization.fill_rules.* 5/5

Bug:angleproject:2352

Change-Id: I5a8869751ea0d787cc266ae12422633106e39983
Reviewed-on: https://chromium-review.googlesource.com/959118
Commit-Queue: Luc Ferron <lucferron@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>