This is a reland of c6c86944
The code offset is allowed to be null if there is no function in the module.

Original change's description:
> [wasm] Fix code offset after module cache hit
>
> If the module cache was hit, we didn't set the code offset in the
> decoded module. Hence it was reported as 0 to the DevTools frontend,
> leading to subsequent errors.
> Note that this error can only happen if multiple isolates share the same
> module, which we cannot easily test in v8. Sharing within a single
> isolate is implemented via the script cache, so we won't report another
> script via CDP.
>
> R=thibaudm@chromium.org
>
> Bug: chromium:1114143
> Change-Id: I3218a3b12cf5be09d685e3f371f858ab799cef80
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2519560
> Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
> Commit-Queue: Clemens Backes <clemensb@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#70967}

Bug: chromium:1114143
Change-Id: I4609cfc61fbd8b5092781dc9308f5651bcc76c42
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2517695
Commit-Queue: Thibaud Michaud <thibaudm@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70991}