src: add a condition if the argument of DomainToUnicode is

PR-URL: nodejs/node#49097
Refs: nodejs/node#46410
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Deokjin Kim <deokjin81.kim@gmail.com>

graal-nodejs/src/node_url.cc

@@ -95,6 +95,11 @@ void BindingData::DomainToUnicode(const FunctionCallbackInfo<Value>& args) {
   CHECK(args[0]->IsString());
 
   std::string input = Utf8Value(env->isolate(), args[0]).ToString();
+  if (input.empty()) {
+    return args.GetReturnValue().Set(
+        String::NewFromUtf8(env->isolate(), "").ToLocalChecked());
+  }
+
   // It is important to have an initial value that contains a special scheme.
   // Since it will change the implementation of `set_hostname` according to URL
   // spec.