MD Settings: clarify "controlled by" logic

chrome/test/data/webui/settings/controlled_radio_button_tests.js

 // Copyright 2016 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.
 
 suite('controlled radio button', function() {
   /** @type {ControlledRadioButtonElement} */
   var radioButton;
 
   /** @type {!chrome.settingsPrivate.PrefObject} */
   var pref = {
     key: 'test',
     type: chrome.settingsPrivate.PrefType.BOOLEAN,
     value: true
   };
 
   setup(function() {
     PolymerTest.clearBody();
     radioButton = document.createElement('controlled-radio-button');
     radioButton.set('pref', pref);
     document.body.appendChild(radioButton);
   });
 
   test('disables when pref is managed', function() {
-    radioButton.set('pref.policyEnforcement',
-                    chrome.settingsPrivate.PolicyEnforcement.ENFORCED);
+    radioButton.set('pref.enforcement',
+                    chrome.settingsPrivate.Enforcement.ENFORCED);
     Polymer.dom.flush();
     assertTrue(radioButton.$$('paper-radio-button').disabled);
     assertFalse(!!radioButton.$$('cr-policy-pref-indicator'));
 
     radioButton.set('name', 'true');
     Polymer.dom.flush();
     assertTrue(!!radioButton.$$('cr-policy-pref-indicator'));
 
-    radioButton.set('pref.policyEnforcement', undefined);
+    radioButton.set('pref.enforcement', undefined);
     Polymer.dom.flush();
     assertFalse(radioButton.$$('paper-radio-button').disabled);
     assertEquals('none',
                  radioButton.$$('cr-policy-pref-indicator').style.display);
   });
 });