Revert of [heap] Re-enable black allocation when finalizing marking. (patchset #1 id:1 of https://codereview.chromium.org/2202993002/ )

Reason for revert:
Crashes on tree.

Original issue's description:
> [heap] Re-enable black allocation when finalizing marking.
>
> BUG=chromium:630386
> LOG=n
>
> Committed: https://crrev.com/2c75cfd731e11daa649faf2e91cbb84767b11f8e
> Cr-Commit-Position: refs/heads/master@{#38240}

TBR=ulan@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:630386

Review-Url: https://codereview.chromium.org/2204593005
Cr-Commit-Position: refs/heads/master@{#38243}