cros: Only preload the lock screen; do not reuse it.

chrome/browser/resources/chromeos/login/lock.js

 // Copyright (c) 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 Login UI based on a stripped down OOBE controller.
  */
 
 <include src="login_shared.js">
 
@@ skipping 56 matching lines @@
     },
 
     /**
      * Notification from the host that the PIN keyboard will be used in the
      * lock session so it should also get preloaded.
      */
     preloadPinKeyboard: function() {
       showPinKeyboardAsync();
     },
 
-    /**
-     * Called when a preloaded webview (this) instance is being reused to
-     * display a new lock screen session. This will also be called when a
-     * lock screen has been preloaded and is being displayed for the first
-     * time.
-     */
-    reload: function() {
-      // Sending accountPickerReady displays the webui. Wait for the next
-      // animation frame so the user does not see any state from the previous
-      // instance.
-      requestAnimationFrame(function() {
-        chrome.send('accountPickerReady');
-      });
-    },
-
-    /**
-     * Called when the lock screen has been dismissed but this webview will stay
-     * in memory. The webview will be reused when Oobe.reload() is called.
-     */
-    teardown: function() {
-      // The PIN keyboard will disable the virtual keyboard. Make sure to
-      // revert the force disable when hiding the lock screen.
-      chrome.send('setForceDisableVirtualKeyboard', [false]);
-    },
-
     // Dummy Oobe functions not present with stripped login UI.
     initializeA11yMenu: function(e) {},
     handleAccessibilityLinkClick: function(e) {},
     handleSpokenFeedbackClick: function(e) {},
     handleHighContrastClick: function(e) {},
     handleScreenMagnifierClick: function(e) {},
     setUsageStats: function(checked) {},
     setOemEulaUrl: function(oemEulaUrl) {},
     setTpmPassword: function(password) {},
     refreshA11yInfo: function(data) {},
 
     /**
      * Reloads content of the page.
      * @param {!Object} data New dictionary with i18n values.
      */
     reloadContent: function(data) {
       loadTimeData.overrideValues(data);
       i18nTemplate.process(document, loadTimeData);
       Oobe.getInstance().updateLocalizedContent_();
     },
   };
 });