MD User Manager: Default focused element in add person page and import user dialog.

chrome/browser/resources/md_user_manager/import_supervised_user.js

 // Copyright 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 'import-supervised-user' is a popup that allows user to select
  * a supervised profile from a list of profiles to import on the current device.
  */
 (function() {
 /**
@@ skipping 59 matching lines @@
       if (a.onCurrentDevice != b.onCurrentDevice)
         return a.onCurrentDevice ? 1 : -1;
       return a.name.localeCompare(b.name);
     });
 
     this.supervisedUserIndex_ = NO_USER_SELECTED;
 
     this.signedInUser_ = signedInUser || null;
     if (this.signedInUser_)
       this.popupHidden_ = false;
+
+    this.async(function() {
+      this.$$('paper-listbox').focus();
+    }.bind(this));
   },
 
   /**
    * Computed binding that returns the appropriate import message depending on
    * whether or not there are any supervised users to import.
    * @param {!Array<!SupervisedUser>} supervisedUsers
    * @private
    * @return {string}
    */
   getMessage_: function(supervisedUsers) {
@@ skipping 27 matching lines @@
     var supervisedUser = this.supervisedUsers_[this.supervisedUserIndex_];
     if (this.signedInUser_ && supervisedUser) {
       this.popupHidden_ = true;
       // Event is caught by create-profile.
       this.fire('import', {supervisedUser: supervisedUser,
                            signedInUser: this.signedInUser_});
     }
   }
 });
 })();