Update to use cap API.

git-svn-id: http://svn.automattic.com/wordpress/trunk@3095 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/classes.php

@@ -619,7 +619,7 @@ class WP_Query {
 				} else {
 					if ('draft' == $status) {
 						// User must have edit permissions on the draft to preview.
-						if (! user_can_edit_post($user_ID, $this->posts[0]->ID)) {
+						if (! current_user_can('edit_post', $this->posts[0]->ID)) {
 							$this->posts = array();
 						} else {
 							$this->is_preview = true;