The logic for wrapper compilation is the same in the sync and
async cases. Moreover, when moving wasm off the GC heap, we'll
initially skip serializing the wrappers, and regenerate them,
using the same logic, at deserialization.

Longer term, we intend to make the serialization format for wasm
more resilient wrt V8 versioning, time at which this separation
will continue playing a role: cross-v8 versions, wrappers will
be recompiled (instead of deserialzied), while wasm code may just
be deserialized.

Bug: v8:6876
Change-Id: I8d9ba835e7c83bb8d1f47163f62396a6fa17661d
Reviewed-on: https://chromium-review.googlesource.com/755542Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Mircea Trofin <mtrofin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49198}