BUG=angleproject:963

Change-Id: I1ba418e7540b9c3ac6611aa3e4f0c1ca27557a1a
Reviewed-on: https://chromium-review.googlesource.com/267734Reviewed-by: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tested-by: Jamie Madill <jmadill@chromium.org>