[wasm][eh] Handle exceptions during value encoding

Handle the case where getting a value in the iterable object that
encodes the values throws an exception.

R=ahaas@chromium.org

Bug: chromium:1347073
Change-Id: Ie660ab04148d5fd3508397ae6e08130496f61b74
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3788097
Commit-Queue: Thibaud Michaud <thibaudm@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81974}

src/wasm/wasm-js.cc

@@ -1754,6 +1754,8 @@ void EncodeExceptionValues(v8::Isolate* isolate,
   auto values = arg.As<Object>();
   for (int i = 0; i < signature->length(); ++i) {
     MaybeLocal<Value> maybe_value = values->Get(context, i);
+    i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
+    if (i_isolate->has_scheduled_exception()) return;
     Local<Value> value = maybe_value.ToLocalChecked();
     i::wasm::ValueType type = signature->get(i);
     switch (type.kind()) {

test/mjsunit/regress/wasm/regress-1347073.js

+// Copyright 2022 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var values = [];
+Object.prototype.__defineGetter__(0, function() {
+  throw new Error('foo');
+});
+let tag = new WebAssembly.Tag({parameters: ['externref']});
+assertThrows(() => new WebAssembly.Exception(tag, values), Error, 'foo');