Function validate

web/static/components/angularjs/angular.js:16886–16889

(ctrl, validatorName, validity, value)

// A helper function to call $setValidity and return the value / undefined,
// a pattern that is repeated a lot in the input validation logic.
function validate(ctrl, validatorName, validity, value){
  ctrl.$setValidity(validatorName, validity);
  return validity ? value : undefined;
}

function testFlags(validity, flags) {
  var i, flag;