R=marja@chromium.org

Bug: v8:6509
Change-Id: If8be12e2ce6c00de0bdee38ab721ef5b7b47efe5
Reviewed-on: https://chromium-review.googlesource.com/556239Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46331}