Jetpack Sync: Make the tests pass on the .com side (#10111)

* Jetpack Sync: Make the tests pass on the .com side

* Minor space fix

* Make spacing equal to wpcom file

sync/class.jetpack-sync-module-themes.php

@@ -357,7 +357,7 @@ public function init_full_sync_listeners( $callable ) {
 		add_action( 'jetpack_full_sync_theme_data', $callable );
 	}
 
-	public function sync_theme_support( $new_name, $new_theme, $old_theme = null ) {
+	public function sync_theme_support( $new_name, $new_theme = null, $old_theme = null ) {
 		// Previous theme support got added in WP 4.5
 		$previous_theme = false;
 		if ( $old_theme instanceof WP_Theme ) {
@@ -613,4 +613,4 @@ private function get_delete_theme_call() {
 	private function is_theme_switch() {
 		return did_action( 'after_switch_theme' );
 	}
-}
+}