This reverts commit 8325f86d.

Reason for revert: Speculative revert for chromium:1336850.

Original change's description:
> [heap] Sweep code pages on the background thread
>
> We already make code pages writable & executable for concurrent
> Sparkplug. We can use the same mechanism for sweeping of code pages on
> the background thread, instead of scheduling incremental tasks on the
> main thread. This allows us to remove almost all special
> handling for code pages in the sweeper and allows us to off-load more
> work from the main thread.
>
> Bug: v8:12967
> Change-Id: Idb8e9f8e2eadbec26a386f2de683a80087f671f3
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695557
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#81139}

Bug: v8:12967, chromium:1336850
Change-Id: I1fb775892c2679984221efa7ceb682800c88cb2f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3707274
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81213}