Compilation only stores whether an error has been found, but not the
exact error or it's location. This is generated by running a validation
pass once all wire bytes have been received.
This unifies error messages by removing one more location where we
generate compilation error messages, and makes it deterministic because
a) we always report the error in the first failing function, and
b) if names are present, the error message will always contain the
   function name.

R=titzer@chromium.org

Bug: chromium:926311, v8:8814
Change-Id: I79551b8bb73dcee503484de343a3ada60a6add4f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1521112
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60242}