This reverts commit a4105a43.

Reason for revert: GC stress failures (https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Mac64%20GC%20Stress/3097)

Original change's description:
> [wasm] Implement handling of exported/imported exceptions.
> 
> This implements the proper semantics for matching exported/imported
> exceptions by using the notion of an "exception tag" that is global to
> the system. It can be used to match exceptions in one module against
> exceptions declared and/or thrown in another module (or instance).
> 
> R=​clemensh@chromium.org
> TEST=mjsunit/wasm/exceptions-shared
> BUG=v8:8091
> 
> Change-Id: I37586d7be5d5e6169b3418dfbc415b26dd4750dd
> Reviewed-on: https://chromium-review.googlesource.com/1226976
> Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
> Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#55940}

TBR=mstarzinger@chromium.org,clemensh@chromium.org

Change-Id: I5ef19ea3b67f470f2d7807810110d75415ba9ed6
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:8091
Reviewed-on: https://chromium-review.googlesource.com/1227933Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55942}