Reuse sweeping+free list allocation code from
SweepAndRetryAllocation in RawSlowRefillLinearAllocationArea.

Share code such that bugs like the linked one are less likely to
happen.

Bug: chromium:1020981
Change-Id: I0abfaa9f7a8f2b62ad24ca85774130f354104e93
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1901277Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64829}