This will be needed later for concurrent marking

Bug: chromium:1056170
Change-Id: Iab7812d7ac8a30e3a54bd7c4b739077b293db775
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2287869
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68796}