This CL separates logic for promoting all of new space during fast
promotion out of the heap and into a new dedicated
PromoteYoungGenerationGC class.

It currently assumes SemiSpaceNewSpace and will need to be extended with
support for PagedNewSpace.

Bug: v8:12612
Change-Id: I0e65c034b444634a31b3c00df0a4b558612f023f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644610Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80492}