title: Ionic 4 setRoot with Angular Router
body: <p>I'm upgrading my Ionic 3 project to the latest Ionic 4 and I have some trouble with Routing. In Ionic 3 I used setRoot just like this: </p>
  
  <pre><code>handler: () =&gt; navCtrl.parent.parent.setRoot(HomePage, 'logout', {animate: true})
  </code></pre>
  
  <p>The latest navCtrl of Ionic 4 has only goBack, goForward and goRoot, and I don't understand how to use parent. I found ActivatedRoute in Angular, but I don't think this is the right way. How can I do?</p>