This change also modifies the way references are typed: Instead of
using the static type (which may be a generic type like anyref) the
actual type based on the referenced object is used.
While this is very useful for arrays and structs (and somewhat nice for
i31 not just being a number but also having some type information), it
means for non-null values that the reference type is "not nullable",
so it will show e.g. "ref $type0" although the static type  might be
"ref null $type0".

Bug: v8:7748
Change-Id: I00c3258b0da6f89ec5efffd2a963889b1f341c3a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3852485Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Matthias Liedtke <mliedtke@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82753}