Browser tests for the quick_unlock settings pages.

chrome/browser/resources/settings/people_page/lock_state_behavior.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.
 
 /**
  * @fileoverview
  * Contains utilities that help identify the current way that the lock screen
  * will be displayed.
  */
 
@@ skipping 19 matching lines @@
 
     /**
      * True/false if there is a PIN set; undefined if the computation is still
      * pending. This is a separate value from selectedUnlockType because the UI
      * can change the selectedUnlockType before setting up a PIN.
      * @type {boolean|undefined}
      */
     hasPin: {
       type: Boolean,
       notify: true
-    }
+    },
+
+    /**
+     * Interface for chrome.quickUnlockPrivate calls. May be overriden by tests.
+     * @private
+     */
+    quickUnlockPrivate_: {
+      type: Object,
+      value: chrome.quickUnlockPrivate
+    },
   },
 
   /** @override */
   attached: function() {
     this.boundOnActiveModesChanged_ = this.updateUnlockType_.bind(this);
-    chrome.quickUnlockPrivate.onActiveModesChanged.addListener(
+    this.quickUnlockPrivate_.onActiveModesChanged.addListener(
         this.boundOnActiveModesChanged_);
 
     this.updateUnlockType_();
   },
 
   /** @override */
   detached: function() {
-    chrome.quickUnlockPrivate.onActiveModesChanged.removeListener(
+    this.quickUnlockPrivate_.onActiveModesChanged.removeListener(
         this.boundOnActiveModesChanged_);
   },
 
   /**
    * Updates the selected unlock type radio group. This function will get called
    * after preferences are initialized, after the quick unlock mode has been
    * changed, and after the lockscreen preference has changed.
    *
    * @private
    */
   updateUnlockType_: function() {
-    chrome.quickUnlockPrivate.getActiveModes(function(modes) {
+    this.quickUnlockPrivate_.getActiveModes(function(modes) {
       if (modes.includes(chrome.quickUnlockPrivate.QuickUnlockMode.PIN)) {
         this.hasPin = true;
         this.selectedUnlockType = LockScreenUnlockType.PIN_PASSWORD;
       } else {
         this.hasPin = false;
         this.selectedUnlockType = LockScreenUnlockType.PASSWORD;
       }
     }.bind(this));
   },
 };