code: func throwJSException(msg interface{}) otto.Value {
  	val, err := otto.ToValue(msg)
  	if err != nil {
  		log.Error("Failed to serialize JavaScript exception", "exception", msg, "err", err)
  	}
  	panic(val)
  }
docs: // throwJSException panics on an otto.Value. The Otto VM will recover from the
  // Go panic and throw msg as a JavaScript error.