R=ahaas@chromium.org

Bug: 
Change-Id: Ic2331617624ce724ba33e07a1a42ebe2549f8054
Reviewed-on: https://chromium-review.googlesource.com/586547Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46903}