ValueSerializer: promote scheduled exception if the caller throws one.

src/value-serializer.cc

 // Copyright 2016 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.
 
 #include "src/value-serializer.h"
 
 #include <type_traits>
 
 #include "src/base/logging.h"
 #include "src/conversions.h"
@@ skipping 726 matching lines @@
 void ValueSerializer::ThrowDataCloneError(
     MessageTemplate::Template template_index, Handle<Object> arg0) {
   Handle<String> message =
       MessageTemplate::FormatMessage(isolate_, template_index, arg0);
   if (delegate_) {
     delegate_->ThrowDataCloneError(Utils::ToLocal(message));
   } else {
     isolate_->Throw(
         *isolate_->factory()->NewError(isolate_->error_function(), message));
   }
+  if (isolate_->has_scheduled_exception()) {
+    isolate_->PromoteScheduledException();
+  }
 }
 
 ValueDeserializer::ValueDeserializer(Isolate* isolate,
                                      Vector<const uint8_t> data)
     : isolate_(isolate),
       position_(data.start()),
       end_(data.start() + data.length()),
       id_map_(Handle<SeededNumberDictionary>::cast(
           isolate->global_handles()->Create(
               *SeededNumberDictionary::New(isolate, 0)))) {}
@@ skipping 722 matching lines @@
   if (stack.size() != 1) {
     isolate_->Throw(*isolate_->factory()->NewError(
         MessageTemplate::kDataCloneDeserializationError));
     return MaybeHandle<Object>();
   }
   return scope.CloseAndEscape(stack[0]);
 }
 
 }  // namespace internal
 }  // namespace v8