title: Not able to listen to a broadcast Stream
body: <p>My standard stream:</p>
  
  <pre><code>var stream = (StreamController&lt;int&gt;()..add(1)).stream;
  stream.listen(print); // prints 1
  </code></pre>
  
  <p>My broadcast stream:</p>
  
  <pre><code>var stream = (StreamController&lt;int&gt;.broadcast()..add(1)).stream;
  stream.listen(print); // doesn't print anything
  </code></pre>