build(examples): upgrade to protractor 4.0.9 (#12803)

closes #12798

modules/@angular/examples/forms/ts/reactiveRadioButtons/e2e_test/reactive_radio_button_spec.ts

@@ -6,11 +6,12 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
+import {ElementArrayFinder, browser, by, element} from 'protractor';
 import {verifyNoBrowserErrors} from '../../../../_common/e2e_util';
 
 describe('radioButtons example', () => {
   afterEach(verifyNoBrowserErrors);
-  let inputs: protractor.ElementArrayFinder;
+  let inputs: ElementArrayFinder;
 
   beforeEach(() => {
     browser.get('/forms/ts/reactiveRadioButtons/index.html');