Introduce separate counters for young and old array buffer bytes. They
are used to keep the counter stable during sweeping when the array
buffer lists are moved to the concurrent thread for sweeping.

Bug: v8:10064
Change-Id: I0f11a634341873b4d21759c284c55beb26fe30a5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2045511
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66204}