fix quick unlock config in options

chrome/browser/resources/settings/people_page/lock_screen.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
  * 'settings-lock-screen' allows the user to change how they unlock their
  * device.
  *
  * Example:
@@ skipping 74 matching lines @@
   browserProxy_: null,
 
   /** selectedUnlockType is defined in LockStateBehavior. */
   observers: ['selectedUnlockTypeChanged_(selectedUnlockType)'],
 
   /** @override */
   attached: function() {
     // currentRouteChanged is not called during the initial navigation. If the
     // user navigates directly to the lockScreen page, we still want to show the
     // password prompt page.
-    this.currentRouteChanged(settings.Route.LOCK_SCREEN,
-        settings.Route.LOCK_SCREEN);
+    this.currentRouteChanged(settings.getCurrentRoute(),
+        settings.getCurrentRoute());

[Dan Beam, 2017/02/17 02:45:17]

say whattttt?

[xiaoyinh(OOO Sep 11-29), 2017/02/17 19:33:46]

I'm not sure why we want to explicitly set the route "LOCK_SCREEN" when the
element is attached.
In other places, it seems to use navigateTo to change route.

This change should not impact settings functionality though, if I understand it
correctly, there're 2 ways to navigate to lock screen page:

1. Navigate from people page:
It will setCurrentRoute to LOCK_SCREEN in people_page.js by using
settings.navigateTo(settings.Route.LOCK_SCREEN);

2. Navigate to lockscreen directly by using chrome://md-settings/lockScreen.
route.js will call initializeRouteFromUrl and set the current route to
LOCK_SCREEN.

Either way, the currentRoute is set to LOCK_SCREEN before calling attached().

The change is mainly for options page, because we want to pre-load the lock
screen element now, the attached function will get called even though the quick
unlock overlay is still hidden, setting the route to LOCK_SCREEN will open a
(hidden)password dialog before we want to configure the pin in options. 

     this.browserProxy_ = settings.FingerprintBrowserProxyImpl.getInstance();
   },
 
   /**
    * Overridden from settings.RouteObserverBehavior.
    * @param {!settings.Route} newRoute
    * @param {!settings.Route} oldRoute
    * @protected
    */
   currentRouteChanged: function(newRoute, oldRoute) {
@@ skipping 86 matching lines @@
     e.preventDefault();
     this.$.setupPin.open();
     this.writeUma_(LockScreenProgress.CHOOSE_PIN_OR_PASSWORD);
   },
 
   /** @private */
   onEditFingerprints_: function() {
     settings.navigateTo(settings.Route.FINGERPRINT);
   },
 });