md settings: Change action link to button on lock screen.

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 200 matching lines @@
       this.$$('#unlockType').focus();
   },
 
   /** @private */
   onPinSetupDone_: function() {
     this.$.setupPin.close();
   },
 
   /** @private */
   onSetupPinClosed_: function() {
-    this.$$('#setupPinLink').focus();
+    this.$$('#setupPinButton').focus();
   },
 
   /**
    * Returns true if the setup pin section should be shown.
    * @param {!string} selectedUnlockType The current unlock type. Used to let
    *     Polymer know about the dependency.
    * @private
    */
   showConfigurePinButton_: function(selectedUnlockType) {
     return selectedUnlockType === LockScreenUnlockType.PIN_PASSWORD;
@@ skipping 88 matching lines @@
   /**
    * @param {boolean} easyUnlockEnabled
    * @param {boolean} proximityDetectionAllowed
    * @private
    */
   getShowEasyUnlockToggle_: function(
       easyUnlockEnabled, proximityDetectionAllowed) {
     return easyUnlockEnabled && proximityDetectionAllowed;
   },
 });