message: feat: make the provider valid/invalid classes in sync with messages
diff: @@ -304,6 +304,18 @@ export const ValidationProvider = {
  const names = VeeValidate.config.classNames;
  return Object.keys(this.flags).reduce((classes, flag) => {
  const className = (names && names[flag]) || flag;
  + if (flag === 'invalid') {
  + classes[className] = !!this.messages.length;
  +
  + return classes;
  + }
  +
  + if (flag === 'valid') {
  + classes[className] = !this.messages.length;
  +
  + return classes;
  + }
  +
  if (className) {
  classes[className] = this.flags[flag];
  }
  