This reverts commit c3f18ae6.

Reason for revert: Speculative revert for https://luci-milo.appspot.com/ui/inv/build-8807661142690641489/test-results?q=conformance%2Fogles%2FGL%2FgreaterThanEqual%2FgreaterThanEqual_001_to_008.html

Original change's description:
> Reland "cppgc: Enable pointer compression by default on Desktop"
>
> - The data race on atomic memcpying/memsetting was fixed;
> - All the known alignment issues in Blink were fixed;
> - Several perf optimizations were applied.
>
> Original change's description:
> > cppgc: Enable pointer compression by default on Desktop
> >
> > The CL enables pointer compression in Oilpan.
> >
> > For sherrifs: the CL may cause some slight perf regressions (likely
> > blink_perf.*), due to slightly higher cost of compression and
> > decomrpession.
> >
> > Speedometer2 is not expected to regress, as was checked locally. Such a
> > slight performance degradation is compensated by memory savings that are
> > expected to be around 10-20% of Oilpan committed size (~2.5-5% of Renderer
> > PMF).
>
> Bug: chromium:1325007
> Change-Id: I5fa9a06cb1fa5141f4e2b22e710007e2404a176b
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3762567
> Auto-Submit: Anton Bikineev <bikineev@chromium.org>
> Commit-Queue: Anton Bikineev <bikineev@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#81914}

Bug: chromium:1325007
Change-Id: I15baa011500a2156871277c644a004b9cacfd5f4
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3783991
Owners-Override: Leszek Swirski <leszeks@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#81930}