BUG=angleproject:851

Change-Id: I68a47b8343a29e42c0a69ca3f2a6cb5054d03782
Reviewed-on: https://chromium-review.googlesource.com/362775Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>