The bit is immutable and set during construction of the meta data. The
main thread needs to query this bit while the concurrent marker may be
running.

Bug: chromium:1319210
Change-Id: I811d8048a61a3c682245b34302b6078d91f9662a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3599489Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80149}