Revert of Reland of Remove slots that point to unboxed doubles from the StoreBuffer...

Revert of Reland of Remove slots that point to unboxed doubles from the StoreBuffer/SlotsBuffer. (patchset #3 id:40001 of https://codereview.chromium.org/988363002/)

Reason for revert:
Increased rate of Chrome crashes. Requires further investigation.

Original issue's description:
> Reland of Remove slots that point to unboxed doubles from the StoreBuffer/SlotsBuffer.
>
> The problem is that 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, chromium:465273
> LOG=Y
>
> Committed: https://crrev.com/6d0677d845c47ab9fa297de61d0e3d8e5480a02a
> Cr-Commit-Position: refs/heads/master@{#27141}

TBR=hpayer@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:454297, chromium:465273

Review URL: https://codereview.chromium.org/1004623003

Cr-Commit-Position: refs/heads/master@{#27207}