BUG=angleproject:747

Change-Id: I775265a7494aedd19ca4f18019e3b3181bfb12e9
Reviewed-on: https://chromium-review.googlesource.com/410135
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>