This is a reland of 0f2d22dd

Original change's description:
> [wasm] Improve module code size sampling approach.
> 
> This samples module code sizes at GC time instead of during destruction.
> It hence makes sure that we also receive samples for long-lived modules
> which would otherwise die with the Isolate and never be finalized. Note
> that this approach is still biased and just a stop-gap until we have a
> sampling tick based on actual wall-clock time.
> 
> R=clemensh@chromium.org
> 
> Change-Id: I9558d383a5aada8876bc9cbf63baca771dbe5c28
> Reviewed-on: https://chromium-review.googlesource.com/1141866
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
> Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#54554}

Change-Id: I1863e94bbe91c89c248ddf8fc700ff91bc3593b2
Reviewed-on: https://chromium-review.googlesource.com/1143344Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54572}