bindings: Support "attribute FrozenArray<T>?"

Adds a quick hack to support a case of "attribute FrozenArray<T>?".

Bug: 1028047
Change-Id: Ib3cecc4beb6bcc0fb0dbc667aca595454cc90c86
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1933866
Reviewed-by: Hitoshi Yoshida <peria@chromium.org>
Commit-Queue: Yuki Shiino <yukishiino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#718676}
void V8TestObject::IndexedPropertyDefinerCallback(
    uint32_t index,
    const v8::PropertyDescriptor& desc,
    const v8::PropertyCallbackInfo<v8::Value>& info) {
  if (desc.has_get() || desc.has_set()) {
    V8SetReturnValue(info, v8::Null(info.GetIsolate()));
    if (info.ShouldThrowOnError()) {
      ExceptionState exception_state(info.GetIsolate(),
                                     ExceptionState::kIndexedSetterContext,
                                     "TestObject");
      exception_state.ThrowTypeError("Accessor properties are not allowed.");
    }
    return;
  }

}

void V8TestObject::IndexedPropertyDefinerCallback(
    uint32_t index,
    const v8::PropertyDescriptor& desc,
    const v8::PropertyCallbackInfo<v8::Value>& info) {
  if (desc.has_get() || desc.has_set()) {
    V8SetReturnValue(info, v8::Null(info.GetIsolate()));
    if (info.ShouldThrowOnError()) {
      ExceptionState exception_state(info.GetIsolate(),
                                     ExceptionState::kIndexedSetterContext,
                                     "TestObject");
      exception_state.ThrowTypeError("Accessor properties are not allowed.");
    }
    return;
  }

}
