This is a partial reland of https://crrev.com/c/3597106

With this change, an existing Script from the compilation cache can be
reused after its top-level SharedFunctionInfo was discarded, but only if
the new script is parsed on the main thread (not deserialized from code
cache data, and not parsed on a background thread).

Bug: v8:12808
Change-Id: I1edaee2095306a89e2c3b91f2fd01ac053f3c770
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3689348Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/main@{#81472}