When a LocalHeap is destroyed, we update (publish) the changes
in the TypedSlots, this need to be protected by a mutex, since
we may read the RecordRelocSlot in a different thread.

Bug: v8:12054, v8:12411, chromium:1272364
Change-Id: Id1684dad3ed9e02c597099c440d1fbfdbd8c47ce
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3297892
Commit-Queue: Victor Gomes <victorgomes@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78059}