Improve component typesript example

apps/baseline/README.md

@@ -3,6 +3,11 @@
 The easiest way to create a simple Reactive Form is to use a single Angular component to build and display the form. In this example application, an asynchronous call to an API is simulated. The `Contact` object thus obtained is used to create and initialize a `FormGroup` using the Angular `FormBuilder`.
 
 ```typescript
+export class AppComponent implements OnInit, OnDestroy {
+  form: FormGroup;
+
+  private subscription: Subscription;
+
   public ngOnInit() {
     this.subscription = this.service
       .loadContact()
@@ -47,6 +52,7 @@ The easiest way to create a simple Reactive Form is to use a single Angular comp
   get addresses(): FormArray {
     return this.form.get('addresses') as FormArray;
   }
+}
 ```
 
 The component's template remders input controls for the Contact's name, and iterates over the array of addresses to render controls to edit each one.