MDL-60287 scssphp: upgraded to 0.6.7

lib/scssphp/Server.php

@@ -2,7 +2,7 @@
 /**
  * SCSSPHP
  *
- * @copyright 2012-2015 Leaf Corcoran
+ * @copyright 2012-2017 Leaf Corcoran
  *
  * @license http://opensource.org/licenses/MIT MIT
  *
@@ -457,7 +457,7 @@ class Server
      */
     public static function serveFrom($path)
     {
-        $server = new self($path);
+        $server = new static($path);
         $server->serve();
     }
 }