ArrayBuffer backing stores will instead use the virtual memory cage and
be referenced through offsets rather than pointers when the sandbox is
enabled. This will be implemented in an independent CL.

Bug: v8:10391
Change-Id: Icc9781003e53c76dbbf4c84ee165151e4182da4b
Cq-Include-Trybots: luci.v8.try:v8_linux64_heap_sandbox_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3086458Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Samuel Groß <saelo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76348}