Revert of Reland "Filter invalid slots out from the SlotsBuffer after marking." (patchset #2 id:2 of https://codereview.chromium.org/1032833002/)

Reason for revert:
Reverting risky GC changes that block v8 roll.

Original issue's description:
> Reland "Filter invalid slots out from the SlotsBuffer after marking."
>
> > There are two reasons that could cause invalid slots appearance in SlotsBuffer:
> > 1) If GC trims "tail" of an array for which it has already recorded a slots and then migrate another object to the "tail".
> > 2) Tagged slot could become a double slot after migrating of an object to another map with "shifted" fields (for example as a result of generalizing immutable data property to a data field).
>
> > This CL also adds useful machinery that helps triggering incremental write barriers.
>
> > BUG=chromium:454297
> > LOG=Y
>
> NOTRY=true
>
> Committed: https://crrev.com/f86aadd1d45c756467dff8e08a055b462d7a060b
> Cr-Commit-Position: refs/heads/master@{#27433}

TBR=machenbach@chromium.org,ulan@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1041593002

Cr-Commit-Position: refs/heads/master@{#27491}