diff --git a/src/wp-admin/includes/class-wp-upgrader.php b/src/wp-admin/includes/class-wp-upgrader.php
index c137896384..ccd2931f58 100644
--- a/src/wp-admin/includes/class-wp-upgrader.php
+++ b/src/wp-admin/includes/class-wp-upgrader.php
@@ -24,6 +24,8 @@ class WP_Upgrader {
 	public $strings = array();
 	public $skin = null;
 	public $result = array();
+	public $update_count = 0;
+	public $update_current = 0;
 
 	public function __construct($skin = null) {
 		if ( null == $skin )