This CL eliminates managed heap reads from the ByteCodeGraphBuilder
from constants. These reads and serializations are made at serialization
time.

Bug: v8:7790
Change-Id: I5c59ea1f097d11f48994f41ac296cfc64121db25
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1746477
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63169}