title: jQuery UI Autocomplete Widget: modifying response data in "response" event doesn't have any effect
body: <p>From the <a href="http://api.jqueryui.com/autocomplete/#event-response" rel="nofollow noreferrer">JQuery UI docs</a>:</p>
  
  <blockquote>
    <p>(The <code>response</code> event is) triggered after a search completes, before the menu is shown. Useful for local manipulation of suggestion data.</p>
  </blockquote>
  
  <p>And</p>
  
  <blockquote>
    <p>(The <code>ui.content</code> argument) contains the response data and can be modified to change the results that will be shown.</p>
  </blockquote>
  
  <p>Hoewever, if I modify <code>ui.content</code> on the <code>response</code> event it doesn't affect the results shown in the dropdown, instead my code is just ignored. Here's my (test) code:</p>
  
  <pre><code>$('input.autocomplete').autocomplete({
      source: new Array({label: 'test1', value: 'test1'}, {label: 'test2', value: 'test2'}),
      response: function( event, ui ) {
          ui = {content: new Array({label: 'test3', value: 'test3'}, {label: 'test4', value: 'test4'})};
      }
  });
  </code></pre>
  
  <p>In theory, if the term is "t", it should display <em>test3</em> and <em>test4</em> as my autocomplete options, but it doesn't. I get <em>test1</em> and <em>test2</em>.</p>
  
  <p>What am I missing?</p>
  
  <p>I'm using version 1.9.2 in case you want to point me to <a href="https://stackoverflow.com/questions/12788804/jquery-autocomplete-response-method">this thread</a>.</p>