title: Angular change detection is not working after AngularFireAuth signInWithPopup
body: <p>I call AngularFireAuth signInWithPopup like below and on its success, route to another component but in that changes are not detected.</p>
  
  <p>Find complete code here <a href="https://stackblitz.com/edit/cdissue" rel="nofollow noreferrer">https://stackblitz.com/edit/cdissue</a></p>
  
  <p>The first screen has two buttons - 'Go to comp2 without login' &amp; 'Go to comp2 after login'
  First click on the button 'Go to comp2 without login' to go to second screen where two buttons &amp; a count text are there.</p>
  
  <p>Click on the Increment button will increment the count. This is the working fine scenario.</p>
  
  <p>Click 'Go back' to back to screen one then click on the button 'Go to comp2 after login' which will show a popup to login through gmail. After login it will automatically route to screen two.
  You may use the credentials cdissue@gmail.com &amp; @ngularTest to login using gmail</p>
  
  <p>Now the count is not displayed or click on increment doesn't show the count and this is the error scenario  </p>
  
  <pre><code>Observable.fromPromise(
        this.afAuth.auth.signInWithPopup(new firebase.auth.GoogleAuthProvider())
      )
      .pipe(
        first(),
        map( authData =&gt; {
          this.router.navigate(['comp2'])
        })
      ).subscribe();
  </code></pre>