This is a reland of 76f6c276

Original change's description:
> cppgc: Fix data race ObjectSizeTrait
>
> Fix benign race in
>   https://clusterfuzz.com/testcase-detail/5203237072076800
>
> Change-Id: I558b230e4905a48342d8e7cf70d39be5a1b7fdb8
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3306375
> Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Omer Katz <omerkatz@chromium.org>
> Auto-Submit: Michael Lippautz <mlippautz@chromium.org>
> Reviewed-by: Omer Katz <omerkatz@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#78121}

Change-Id: Ifa50f35591b2ae40f11a384f0fb2ff50115b2511
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3306379
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Auto-Submit: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78124}