title: Polymer 1.0 Iron-Ajax
body: <p>I am trying to get data via a php script that works in Polymer 0.5. 
  I just get null response and no errors in Polymer 1.0, below is the code. 
  I have tried modifying the PHP to echo anything but I get no response. 
  hresponse does fire but at that point only the request information is in ajax the response information is null.
  I cannot find an example to see where I have gone wrong.
  Thanks</p>
  
  <pre><code>&lt;iron-ajax
          id="ajax"
          url=""
          params=""
          handle-as="json"
          on-response="hresponse"
          debounce-duration="300"&gt;
  &lt;/iron-ajax&gt;
  
  and the script
  
  setajax:  function(){
     this.$.ajax.url = "Scripts/getnotes.php";
     this.$.ajax.params='{"SN":"VBA056"}';
     this.$.ajax.generateRequest();
  }
  
  hresponse: function(e) {
        console.log(e.detail.response);
        console.log(this.$.ajax.lastResponse);
  }
  </code></pre>