Add missing ClassRegistry import.

Fixes #2757

lib/Cake/Model/Datasource/Session/DatabaseSession.php

@@ -18,6 +18,7 @@
  */
 
 App::uses('CakeSessionHandlerInterface', 'Model/Datasource/Session');
+App::uses('ClassRegistry', 'Utility');
 
 /**
  * DatabaseSession provides methods to be used with CakeSession.

lib/Cake/View/Helper/FormHelper.php

@@ -12,7 +12,7 @@
  * @since       CakePHP(tm) v 0.10.0.1076
  * @license     MIT License (http://www.opensource.org/licenses/mit-license.php)
  */
-
+App::uses('ClassRegistry', 'Utility');
 App::uses('AppHelper', 'View/Helper');
 
 /**