This makes it less likely to break layout tests (and block rolling V8 to
Chromium) by accident.

BUG=v8:8595
NOTRY=true

Change-Id: Ie5d2fad72b5b6dc4e3101114068ad134add2e475
Reviewed-on: https://chromium-review.googlesource.com/c/1379882
Commit-Queue: Marja Hölttä <marja@chromium.org>
Reviewed-by: Sergiy Belozorov <sergiyb@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58305}