message: fix codepath with warning skip in production
diff: @@ -23,8 +23,11 @@ export default class ErrorBag {
  */
  add (error: FieldError | FieldError[]) {
  // handle old signature.
  - if (process.env.NODE_ENV !== 'production' && arguments.length > 1) {
  + if (arguments.length > 1) {
  + if (process.env.NODE_ENV !== 'production') {
  warn('This usage of "errors.add()" is deprecated, please consult the docs for the new signature.');
  + }
  +
  error = {
  field: arguments[0],
  msg: arguments[1],
  