Function validator

test/angular/1.2/angular.js:17153–17163

(value)

  if (isObject(validity)) {
    ctrl.$$hasNativeValidators = true;
    var validator = function(value) {
      // Don't overwrite previous validation, don't consider valueMissing to apply (ng-required can
      // perform the required validation)
      if (!ctrl.$error[validatorName] &&
          !testFlags(validity, ignoreFlags) &&
          testFlags(validity, badFlags)) {
        ctrl.$setValidity(validatorName, false);
        return;
      }
      return value;
    };
    ctrl.$parsers.push(validator);
  }
}