message: docs: make method arguments optional in template syntax example
  PR Close
diff: @@ -66,7 +66,7 @@ export class AppComponent implements AfterViewInit, OnInit {
  currentHero: Hero;
  - deleteHero(hero: Hero) {
  + deleteHero(hero?: Hero) {
  this.alert(`Delete ${hero ? hero.name : 'the hero'}.`);
  }
  @@ -105,18 +105,18 @@ export class AppComponent implements AfterViewInit, OnInit {
  get nullHero(): Hero { return null; }
  - onClickMe(event: KeyboardEvent) {
  + onClickMe(event?: KeyboardEvent) {
  let evtMsg = event ? ' Event target class is ' + (<HTMLElement>event.target).className : '';
  this.alert('Click me.' + evtMsg);
  }
  - onSave(event: KeyboardEvent) {
  + onSave(event?: KeyboardEvent) {
  let evtMsg = event ? ' Event target is ' + (<HTMLElement>event.target).textContent : '';
  this.alert('Saved.' + evtMsg);
  if (event) { event.stopPropagation(); }
  }
  - onSubmit() {/* referenced but not used */}
  + onSubmit(data: any) {/* referenced but not used */}
  product = {
  name: 'frimfram',
  