chrome/browser/resources/options/chromeos_labs.html

<div class="page hidden" id="labsPage">
  <div class="section">
    <div class="section-title" i18n-content="mediaplayer_title"></div>
    <div class="option">
       <table class="option-control-table">
       <tr>
         <td class="option-name"><label><input id="mediaplayer-check"
              pref="settings.labs.mediaplayer" type="checkbox"><span
              i18n-content="mediaplayer"></span></label></td>
       </tr>
       </table>
    </div>
  </div>
  <div class="section">
    <div class="section-title" i18n-content="advanced_file_title"></div>
    <div class="option">
       <table class="option-control-table">
       <tr>
         <td class="option-name"><label><input id="advanced-filesystem-check"
              pref="settings.labs.advanced_filesystem" type="checkbox"><span
              i18n-content="advanced_filesystem"></span></label></td>
       </tr>
       </table>
    </div>
  </div>
</div>