Revert of [heap] Simplify distribution of remaining memory during sweeping & compaction (patchset #2 id:80001 of https://codereview.chromium.org/1653973003/ )

Reason for revert:
Very likely blocking roll: https://codereview.chromium.org/1652413003/

Original issue's description:
> [heap] Simplify distribution of remaining memory during sweeping & compaction
>
> BUG=chromium:524425
> LOG=N
>
> Committed: https://crrev.com/f72923526ccaa8faef5c977267b0c074c4a44dfa
> Cr-Commit-Position: refs/heads/master@{#33668}

TBR=hpayer@chromium.org,mlippautz@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:524425

Review URL: https://codereview.chromium.org/1661723003

Cr-Commit-Position: refs/heads/master@{#33695}