Revert of Revert of [turbofan] Improve memory layout of Node class. (patchset #1 id:1 of https://codereview.chromium.org/856813003/)

Reason for revert:
Revert didn't help.

Original issue's description:
> Revert of [turbofan] Improve memory layout of Node class. (patchset #1 id:1 of https://codereview.chromium.org/828803004/)
>
> Reason for revert:
> Speculative revert to see if win XP recovers. Will reland if not.
>
> Original issue's description:
> > [turbofan] Improve memory layout of Node class.
> >
> > Also gets rid of the reinterpret_cast on this.
> >
> > R=svenpanne@chromium.org
> >
> > Committed: https://crrev.com/f91e8046fad99365c74ccbb39d42de58398dab57
> > Cr-Commit-Position: refs/heads/master@{#26103}
>
> TBR=svenpanne@chromium.org,dcarney@chromium.org,bmeurer@chromium.org
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
>
> Committed: https://crrev.com/dc6f34d83650dce8faa3e82e87c050f12732d4b3
> Cr-Commit-Position: refs/heads/master@{#26106}

TBR=svenpanne@chromium.org,dcarney@chromium.org,bmeurer@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/855723002

Cr-Commit-Position: refs/heads/master@{#26107}