This is a reland of 92f815a8
Safe to reland as-is with task id lifetime fix in
https://chromium-review.googlesource.com/c/v8/v8/+/2437005

Original change's description:
> Reland "[Heap] ScavengerCollector use Jobs."
>
> This is a reland of 9e8c54f8
> Safe to reland as-is with fix in AcquireTaskId
> https://chromium-review.googlesource.com/c/v8/v8/+/2401964
>
> Additional changes are made in the reland:
> -TRACE_GC is be split for background/foreground scope.
> -New IndexGenerator is used for dynamic work assignement.
>
> Original change's description:
> > [Heap] ScavengerCollector use Jobs.
> >
> > No yielding is necessary since the main thread Join()s.
> >
> > max concurrency is determined based on either
> > remaining_memory_chunks_ or global pool size
> > (copied_list_ + promotion_list_)
> >
> > Change-Id: Ie30fa86c44d3224b04df5d79569bce126ce7d96b
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2354390
> > Commit-Queue: Etienne Pierre-Doray <etiennep@chromium.org>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#69746}
>
> Change-Id: Id9d7a5bf3b2337ae4cf1e76770f4b14ebb8ca256
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2399041
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Commit-Queue: Etienne Pierre-Doray <etiennep@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70135}

Change-Id: Id0451b6eca9a125c7695d251d1a7d813e0664dd3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2432071
Commit-Queue: Etienne Pierre-Doray <etiennep@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70238}