Show spinner for constrained signin flow

chrome/browser/resources/inline_login/inline_login.js

 // Copyright 2013 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 Inline login UI.
  */
 
 <include src="../gaia_auth_host/gaia_auth_host.js"></include>
 
@@ skipping 38 matching lines @@
     chrome.send('initialize');
   }
 
   /**
    * Loads auth extension.
    * @param {Object} data Parameters for auth extension.
    */
   function loadAuthExtension(data) {
     authExtHost.load(data.authMode, data, onAuthCompleted);
     $('contents').classList.toggle('loading',
-        data.authMode != cr.login.GaiaAuthHost.AuthMode.DESKTOP);
+        data.authMode != cr.login.GaiaAuthHost.AuthMode.DESKTOP ||

[xiyuan, 2014/06/17 22:58:14]

What does this do? Is it turning off the spinner when authMode ==
AuthMode.DESKTOP? Should we replace the test with "true" to show spinner in all
cases?

[guohui, 2014/06/18 18:44:04]

this is to turn off spinner for full tab signin on desktop. With spinner, the
gaia iframe is initially invisible and thus has 0 height and and since gaia
tries to position the scroll bar based on the frame height thus the page would
scroll to the bottom unexpectedly. 

+        data.constrained == '1');
   }
 
   /**
    * Closes the inline login dialog.
    */
   function closeDialog() {
     chrome.send('dialogClose', ['']);
   }
 
   /**
@@ skipping 23 matching lines @@
     getAuthExtHost: getAuthExtHost,
     isAuthReady: isAuthReady,
     initialize: initialize,
     loadAuthExtension: loadAuthExtension,
     closeDialog: closeDialog,
     handleOAuth2TokenFailure: handleOAuth2TokenFailure
   };
 });
 
 document.addEventListener('DOMContentLoaded', inline.login.initialize);