title: Cross domain error when calling website API from JavaScript in Chrome extension
body: <p>I'm working on a small Chrome extension that will call the Remember the Milk API. Google has a <a href="http://code.google.com/chrome/extensions/getstarted.html" rel="noreferrer">good example</a> using the Flikr API, and I'm using it as the basis for my extension. Their example works perfectly in my browser (latest Chrome on Linux).</p>
  
  <p>When I swap out the Remember the Milk API method names and API key, though, I'm getting the following error: </p>
  
  <pre><code>XMLHttpRequest cannot load http://api.rememberthemilk.com/services/rest/?method=rtm.test.echo&amp;api_key=xxxxxxxxxxxxxxxxxxxxxx&amp;name=Test%20task. 
  Origin chrome-extension://lifnmciajdfhj is not allowed by Access-Control-Allow-Origin.
  </code></pre>
  
  <p>My code looks like this:</p>
  
  <pre><code>    var req = new XMLHttpRequest();
      req.open(
              "GET",
              "http://api.rememberthemilk.com/services/rest/?" +
              "method=rtm.test.echo&amp;" +
              "api_key=xxxxxxxxxxxxxxxxxxxxxxxxxx&amp;" +
              "name=Test%20task", 
              true);
      req.onload = onResponseReceived;
      req.send(null);
  
      function onResponseReceived() {
          console.log("It worked.");
      }
  </code></pre>
  
  <p>Any suggestions? </p>