title: AngularFire Google OAuth not retrieving the user's email
body: <p>I want to get the email address from Google OAuth using AngularFire, but on popup, it's not asking for the email permission.</p>
  
  <p>This is the code from <a href="https://www.firebase.com/docs/web/guide/login/google.html" rel="nofollow noreferrer">Firebase Google auth doc</a></p>
  
  <pre><code>var ref = new Firebase("https://&lt;your-firebase&gt;.firebaseio.com");
  ref.authWithOAuthPopup("google", function(error, authData) { /* Your Code */ }, {
    scope: "email"
  });
  </code></pre>
  
  <p>It works in my angular application, but how can I fix my angular code to do the same?</p>
  
  <pre><code>var ref = new Firebase("https://&lt;your-firebase&gt;.firebaseio.com");
  var auth = $firebaseAuth(ref);
  auth.$authWithOAuthPopup("google").then(function(authData) {
     /* Code */
  }).catch(function(error) {
     console.error("Authentication failed:", error);
  });
  </code></pre>
  
  <p><a href="https://stackoverflow.com/a/28612747/3927928">Link to the same problem with answer</a>, but I don't get the answer and how to fix it.</p>