This implements preliminary handling of exceptions thrown by external
functions that have been imported into the module. Note that handling
internal function is still missing, but tests have been added.

R=clemensh@chromium.org
TEST=cctest/test-run-wasm-exceptions
BUG=v8:8091

Change-Id: I9d07739d8b4715a5643114fd7a868cdd8d72efd0
Reviewed-on: https://chromium-review.googlesource.com/c/1445751
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59199}