WebUI: Add cr-policy-pref-indicator tests

ui/webui/resources/cr_elements/policy/cr_policy_pref_indicator.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview Polymer element for indicating policies that apply to an
  * element controlling a settings preference.
  */
 Polymer({
   is: 'cr-policy-pref-indicator',
 
   behaviors: [CrPolicyIndicatorBehavior, CrPolicyPrefBehavior],
 
   properties: {
     /**
      * Optional preference object associated with the indicator. Initialized to
      * null so that computed functions will get called if this is never set.
      * @type {!chrome.settingsPrivate.PrefObject|undefined}
      */
     pref: Object,
 
     /**
      * Which indicator type to show (or NONE).
      * @type {CrPolicyIndicatorType}
+     * @private
      */
-    indicatorType: {
+    indicatorType_: {
       type: String,
       value: CrPolicyIndicatorType.NONE,
       computed: 'getIndicatorType(pref.controlledBy, pref.enforcement)',
     },
   },
 
   /**
    * @param {CrPolicyIndicatorType} type
-   * @param {!chrome.settingsPrivate.PrefObject} pref
    * @return {string} The tooltip text for |type|.
    * @private
    */
-  getTooltip_: function(type, pref) {
-    var matches = pref && pref.value == pref.recommendedValue;
+  getTooltip_: function(type) {
+    var matches = !!this.pref && this.pref.value == this.pref.recommendedValue;
     return this.getPolicyIndicatorTooltip(
-        type, pref.controlledByName || '', matches);
+        type, this.pref.controlledByName || '', matches);
   },
 
   /**
    * @return {boolean} Whether the policy indicator is on. Useful for testing.
    */
   isActive: function() {
-    return this.isIndicatorVisible(this.indicatorType);
+    return this.isIndicatorVisible(this.indicatorType_);
   },
 });