CompactionSpace::SweepAndRetryAllocation was sweeping the space
without clearing invalidated objects. CompactionSpace is only used
during collections, mark-compact needs invalidated objects in
swept memory to be removed.

Bug: chromium:1020981
Change-Id: Ib5b0edcdd841257cf66af6de8b6a3bf785e5c813
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1900452Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64798}