This reverts commit e14086f0.

Reason for revert: Breaks the build. There is another dependent change that must be reverted first.

Original change's description:
> Revert "[heap] Added per-page array buffer accouting (external memory)."
> 
> This reverts commit d4792e8f.
> 
> Reason for revert: Breaks V8 Linux - gc stress
> 
> https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Linux%20-%20gc%20stress/17056
> 
> Original change's description:
> > [heap] Added per-page array buffer accouting (external memory).
> > 
> > Bug: chromium:845409
> > Change-Id: Ibc568cdc501edf5d84d9c6379aff58be069369af
> > Reviewed-on: https://chromium-review.googlesource.com/1114602
> > Commit-Queue: Rodrigo Bruno <rfbpb@google.com>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#54028}
> 
> TBR=ulan@chromium.org,hpayer@chromium.org,mlippautz@chromium.org,rfbpb@google.com
> 
> Change-Id: I9a354e72df1ab6782bd1c7c4d6b10194bcfaba2b
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: chromium:845409
> Reviewed-on: https://chromium-review.googlesource.com/1115478
> Reviewed-by: Bill Budge <bbudge@chromium.org>
> Commit-Queue: Bill Budge <bbudge@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#54040}

TBR=bbudge@chromium.org,ulan@chromium.org,hpayer@chromium.org,mlippautz@chromium.org,rfbpb@google.com

Change-Id: Iec078656ff3a79a9cee4de046215c55f908c62c7
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:845409
Reviewed-on: https://chromium-review.googlesource.com/1115479Reviewed-by: Bill Budge <bbudge@chromium.org>
Commit-Queue: Bill Budge <bbudge@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54041}