Make code more readable, mainly by using MakeRef & co. and their
overloads.

Bug: v8:7790
Change-Id: Id45a69857a1be106c152615ac6dbc2f8a42fb7e8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2874398Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74401}