This reverts commit 9f18e55f.

Reason for revert: https://ci.chromium.org/p/v8/builders/ci/V8%20Linux64%20TSAN/29660

Original change's description:
> [TurboFan] Don't serialize read-only heap objects
> 
> Read-only heap objects are immutable and immovable. It is safe to access
> these objects directly from the heap. Not having to serialize them
> reduces the time we spend on main thread especially for TurboProp.
> 
> Bug: v8:9684
> Change-Id: Ibabb7076af50c9007d2a8ed57fe257406958fb6a
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1955596
> Reviewed-by: Michael Stanton <mvstanton@chromium.org>
> Reviewed-by: Maya Lekova <mslekova@chromium.org>
> Commit-Queue: Mythri Alle <mythria@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#65490}

TBR=mvstanton@chromium.org,neis@chromium.org,mythria@chromium.org,mslekova@chromium.org

Change-Id: If2d8649cdc083f7d064684352501320a96a1ba2c
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:9684
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1973732Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Commit-Queue: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65492}