test(aio): cleaner approach to reliable Google Analytics e2e tests (#20661)

PR Close #20661

aio/e2e/app.e2e-spec.ts

@@ -80,8 +80,6 @@ describe('site App', function() {
     });
   });
 
-  // TODO(https://github.com/angular/angular/issues/19785): Activate this again
-  // once it is no more flaky.
   describe('google analytics', () => {
 
     it('should call ga with initial URL', done => {

aio/e2e/app.po.ts

@@ -29,10 +29,7 @@ export class SitePage {
   locationPath() { return browser.executeScript('return document.location.pathname') as promise.Promise<string>; }
 
   navigateTo(pageUrl = '') {
-    return browser.get('/' + pageUrl)
-      // We need to tell the index.html not to load the real analytics library
-      // See the GA snippet in index.html
-      .then(() => browser.executeScript('sessionStorage.setItem("__e2e__", true);'));
+    return browser.get('/' + pageUrl);
   }
 
   getDocViewerText() {