WebGL2 Compat: having no 0 divisor is now valid BUG=angleproject:TBD Change-Id: Icb19a685290f4313ad567391cab5152eda91a346 Reviewed-on: https://chromium-review.googlesource.com/544545 Reviewed-by: Zhenyao Mo <zmo@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Zhenyao Mo <zmo@chromium.org>