This introduces a second factory method for allocating new module
objects that are based on existing native modules which are potentially
shared between multiple Isolates.

R=clemensh@chromium.org
TEST=cctest/test-wasm-shared-engine
BUG=v8:7424

Change-Id: I8c74d821542d443a8ad2352cb77b84b445e21acb
Reviewed-on: https://chromium-review.googlesource.com/1126931
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54261}