title: jQuery UI: how to reset dialog title?
body: <p>I want to clear the dialog title, but <code>$('#dialog').dialog('option', 'title', ' ');</code> doesn't work as expected, it will make the dialog title very thin, what is the proper way to clear the title?</p>
  
  <pre><code>&lt;!doctype html&gt;
  &lt;html lang="en"&gt;
      &lt;head&gt;
          &lt;meta charset="utf-8"&gt;
          &lt;title&gt;jQuery UI Dialog - Default functionality&lt;/title&gt;
          &lt;link rel="stylesheet" type="text/css" href="https://ajax.googleapis.com/ajax/libs/jqueryui/1.10.4/themes/cupertino/jquery-ui.css"/&gt;
          &lt;script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"&gt;&lt;/script&gt;
          &lt;script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jqueryui/1.10.4/jquery-ui.min.js"&gt;&lt;/script&gt;
          &lt;script&gt;
              $(function() {
                  $("#b1").click(function(){
                      $('#dialog').dialog('option', 'title', 'test');
                  });
                  $("#b2").click(function(){
                      $('#dialog').dialog('option', 'title', ' ');
                  });
                  $("#b3").click(function(){
                      alert($('#dialog').dialog('option', 'title'));
                  });
                  $("#dialog").dialog();
              });
          &lt;/script&gt;
      &lt;/head&gt;
      &lt;body&gt;
          &lt;div id="dialog"&gt;
              &lt;p&gt;This is a dialog.&lt;/p&gt;
          &lt;/div&gt;
          &lt;input id='b1' type='button' value='set title to test'&gt;
          &lt;input id='b2' type='button' value='clear title'&gt;
          &lt;input id='b3' type='button' value='alert(title);'&gt;
      &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>