Revert of [turbofan] Do not use the self reference for turbofan functions. (patchset #2 id:20001 of https://codereview.chromium.org/2150523002/ )

Reason for revert:
Dependency of the roll unblocking revert https://codereview.chromium.org/2147883003/

Original issue's description:
> [turbofan] Do not use the self reference for turbofan functions.
>
> The self reference requires the allocation of a handle in the macro
> assembler, which is not possible if we instantiate the macro assembler
> in a worker thread.
>
> R=mstarzinger@chromium.org, bmeurer@chromium.org
>
> Committed: https://crrev.com/49ef529b3af50f5daadacdcdcd6be3a307c10af5
> Cr-Commit-Position: refs/heads/master@{#37713}

TBR=bmeurer@chromium.org,mstarzinger@chromium.org,jarin@chromium.org,ahaas@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review-Url: https://codereview.chromium.org/2147943002
Cr-Commit-Position: refs/heads/master@{#37716}