writeExtra method
Implementation
bool writeExtra(dynamic data) {
  var extraEnc = getEncoderFor(data);
  if (extraEnc != null) {
    extraEnc.write(this, data);
    return true;
  }
  return false;
}bool writeExtra(dynamic data) {
  var extraEnc = getEncoderFor(data);
  if (extraEnc != null) {
    extraEnc.write(this, data);
    return true;
  }
  return false;
}