Revert of [turbofan] Improve memory layout of Node class. (patchset #1 id:1 of https...

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

Review URL: https://codereview.chromium.org/856813003

Cr-Commit-Position: refs/heads/master@{#26106}