[cros] Initialize OOBE in parallel when boot animation is disabled.

chrome/browser/resources/chromeos/login/display_manager.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 Display manager for WebUI OOBE and login.
  */
 
 // TODO(xiyuan): Find a better to share those constants.
 /** @const */ var SCREEN_OOBE_NETWORK = 'connect';
@@ skipping 218 matching lines @@
                 oldStep.classList.contains('right')) {
               innerContainer.classList.remove('animation');
               oldStep.classList.add('hidden');
             }
           });
         } else {
           oldStep.classList.add('hidden');
         }
       } else {
         // First screen on OOBE launch.
-        innerContainer.classList.remove('down');
-        innerContainer.addEventListener(
-            'webkitTransitionEnd', function f(e) {
-              innerContainer.removeEventListener('webkitTransitionEnd', f);
-              $('progress-dots').classList.remove('down');
-            });
+        if (innerContainer.classList.contains('down')) {
+          innerContainer.classList.remove('down');
+          innerContainer.addEventListener(
+              'webkitTransitionEnd', function f(e) {
+                innerContainer.removeEventListener('webkitTransitionEnd', f);
+                $('progress-dots').classList.remove('down');
+                chrome.send('loginVisible');
+              });
+        }
         newHeader.classList.remove('right');  // Old OOBE.
-        // Report back first OOBE screen being painted.
-        window.webkitRequestAnimationFrame(function() {
-          chrome.send('loginVisible');
-        });
       }
       this.currentStep_ = nextStepIndex;
       $('oobe').className = nextStepId;
 
       $('step-logo').hidden = newStep.classList.contains('no-logo');
     },
 
     /**
      * Show screen of given screen id.
      * @param {Object} screen Screen params dict,
@@ skipping 305 matching lines @@
     $('add-user-button').disabled = disable;
     $('add-user-button').title = disable ?
         localStrings.getString('disabledAddUserTooltip') : '';
   }
 
   // Export
   return {
     DisplayManager: DisplayManager
   };
 });