R=mstarzinger@chromium.org

Bug: v8:6756
Change-Id: Ic748a4848f66dfcd9b8577d615669b61670e5431
Reviewed-on: https://chromium-review.googlesource.com/647757Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47799}