GL: Adjust disableRenderSnorm condition Current Mesa drivers do not pass the tests when using OpenGL ES contexts. Bug: angleproject:8315 Change-Id: I00e931d0b97917fd7fe02890290f2938d7c872e7 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4834483 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>