chrome/browser/resources/settings/pref_tracker/pref_tracker.html

<link rel="import" href="chrome://resources/polymer/v1_0/polymer/polymer.html">
<link rel="import" href="chrome://md-settings/prefs/prefs_types.html">

<dom-module id="settings-pref-tracker">
  <script src="pref_tracker.js"></script>
</dom-module>