Index: wp-includes/theme.php
===================================================================
--- wp-includes/theme.php	(revision 19970)
+++ wp-includes/theme.php	(working copy)
@@ -1358,6 +1358,22 @@
 }
 
 /**
+ * Update theme modifications for the current theme.
+ *
+ * @since 3.4.0
+ *
+ * @param array $mods Theme modifications.
+ */
+function set_theme_mods( $mods ) {
+	$current = get_theme_mods();
+
+	$mods = wp_parse_args( $mods, $current );
+
+	$theme = get_stylesheet();
+	update_option( "theme_mods_$theme", $mods );
+}
+
+/**
  * Update theme modification value for the current theme.
  *
  * @since 2.1.0