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

With this change, an old entry in the script compilation cache is not
completely removed by CompilationCacheScript::Age(). Instead, its value
is replaced with undefined. In that way, the Script is still accessible
from the table until the garbage collector destroys it and clears the
weak pointer.

Bug: v8:12808
Change-Id: Ib494674e67d0fec455e1fed40499c5cca3b7c0a4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3673426Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/main@{#81084}