Set default focus on offline signin page

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

 // Copyright (c) 2012 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 Oobe signin screen implementation.
  */
 
 login.createScreen('GaiaSigninScreen', 'gaia-signin', function() {
   // GAIA animation guard timer. Started when GAIA page is loaded
@@ skipping 713 matching lines @@
     /**
      * Invoked when the auth host emits 'ready' event.
      * @private
      */
     onAuthReady_: function() {
       this.showViewProcessed_ = false;
       this.startLoadAnimationGuardTimer_();
       this.clearLoadingTimer_();
       this.loading = false;
 
+      if (!$('offline-gaia').hidden)
+        $('offline-gaia').focus();
+
       // Warm up the user images screen.
       Oobe.getInstance().preloadScreen({id: SCREEN_USER_IMAGE_PICKER});
     },
 
     /**
      * Invoked when the auth host emits 'dialogShown' event.
      * @private
      */
     onDialogShown_: function() {
       this.navigation_.disabled = true;
@@ skipping 380 matching lines @@
       if (this.screenMode_ != ScreenMode.AD_AUTH)
         return;
       var adAuthUI = this.getSigninFrame_();
       adAuthUI.setUser(username);
       adAuthUI.setInvalid(errorState);
       this.loading = false;
       Oobe.getInstance().headerHidden = false;
     }
   };
 });