title: Why aren't my parameters getting passed through to a dispatched event?
body: <p>I've set up an event listener like this...</p>
  <pre><code>window.addEventListener('message', parseMessage, false);
  
  var parseMessage = function(rawMessage) {
      console.log(rawMessage.cmd);
  };
  </code></pre>
  <p>And then I'm triggering the event like this:</p>
  <pre><code>var event = new Event('message', {'cmd':&quot;blerg!&quot;});
  
  window.dispatchEvent(event);
  </code></pre>
  <p>The problem is the console.log in parse message is logging out undefined when I am expecting to to log out &quot;blerg!&quot;</p>
  <p>What I am I doing wrong here with the events, how to I pass the 'cmd' message through to the event?</p>