title: unable to set xhr.responseType using chrome 43 beta
body: <p>I have some request that I'm sending the server, and I'm setting the XMLHttpRequest object I created as follows:</p>
  
  <pre><code>var xhr = new XMLHttpRequest();
  xhr.responseType = "blob";
  </code></pre>
  
  <p>This works just fine on the current chrome 42 version, but when I try to run the same code on chrome 43 beta, the xhr.responseType fails to be set with the value "blob". I tried other kinds of response types but it just doesn't work.</p>
  
  <p>Did anyone faced this issue too? 
  Any suggestions?</p>
  
  <p>Thanks.</p>