title: Flutter Future<dynamic> vs. Future<String> subtype error?
body: <p>I just updated Flutter and successfully downloaded my original project from <code>git</code>.  Now I'm getting a weird <code>Future</code> error.  I see mention of it online at github, but with no definitive answer on how to fix. The project doesn't even load.  It reads Future statements from my main.dart file and returns this...</p>
  
  <blockquote>
    <p>[VERBOSE-2:dart_error.cc(16)] Unhandled exception: type
    'Future dynamic' is not a subtype of type 'Future String' where<br>
    Future is from dart:async<br>
    Future is from dart:async<br>
    String is
    from dart:core</p>
  </blockquote>
  
  <p>*** Not sure where error is.  My dart analysis says "Await Only Futures". Here is my futures code which I run before my widgets begin to build...</p>
  
  <pre><code>Future&lt;Null&gt; getData() async{
      FirebaseUser user = await FirebaseAuth.instance.currentUser;
      user = FirebaseAuth.instance.currentUser;
      var userid = user.uid;
      fb.child('users/${userid}').onValue.listen((Event event) {
        if (event.snapshot.value != null) {
          name = event.snapshot.value['displayName'];
          image = event.snapshot.value['image'];
        } else {
          name = "User";
        }
      });
    }
  </code></pre>