Fixing the hiding error bubble animation bug on second opening of create user dialog.

chrome/browser/resources/options/manage_profile_overlay.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.
 
 cr.define('options', function() {
   var Page = cr.ui.pageManager.Page;
   var PageManager = cr.ui.pageManager.PageManager;
   var ArrayDataModel = cr.ui.ArrayDataModel;
 
   /**
@@ skipping 353 matching lines @@
      * Callback which receives the list of existing supervised users. Checks if
      * the currently entered name is the name of an already existing supervised
      * user. If yes, the user is prompted to import the existing supervised
      * user, and the create button is disabled.
      * If the received list is empty, hides the "import" link.
      * @param {Array<Object>} supervisedUsers The list of existing supervised
      *     users.
      * @private
      */
     receiveExistingSupervisedUsers_: function(supervisedUsers) {
+      // After a supervised user has been created and the dialog has been
+      // hidden, this gets called again with a list including
+      // the just-created SU. Ignore, to prevent the "already exists" bubble
+      // from showing up if the overlay is already hidden.
+      if (!this.visible)
+        return;
       $('import-existing-supervised-user-link').hidden =
           supervisedUsers.length === 0;
       if (!$('create-profile-supervised').checked)
         return;
 
       var newName = $('create-profile-name').value;
       var i;
       for (i = 0; i < supervisedUsers.length; ++i) {
         if (supervisedUsers[i].name != newName)
           continue;
@@ skipping 15 matching lines @@
         }
 
         var errorHtml = allOnCurrentDevice ?
             loadTimeData.getStringF(
                 'managedProfilesExistingLocalSupervisedUser') :
             loadTimeData.getStringF(
                 'manageProfilesExistingSupervisedUser',
                 HTMLEscape(elide(newName, /* maxLength */ 50)));
         this.showErrorBubble_(errorHtml, 'create', true);
 
-        $('supervised-user-import-existing').onclick =
-            this.getImportHandler_(supervisedUsers[i], nameIsUnique);
+        if ($('supervised-user-import-existing')) {
+          $('supervised-user-import-existing').onclick =
+              this.getImportHandler_(supervisedUsers[i], nameIsUnique);
+        }
         $('create-profile-ok').disabled = true;
         return;
       }
     },
 
     /**
      * Called in case the request for the list of supervised users fails because
      * of a signin error.
      * @private
      */
@@ skipping 450 matching lines @@
     'updateSignedInStatus',
     'updateSupervisedUsersAllowed',
   ]);
 
   // Export
   return {
     ManageProfileOverlay: ManageProfileOverlay,
     CreateProfileOverlay: CreateProfileOverlay,
   };
 });