* void return type (https://wiki.php.net/rfc/void_return_type)
* Nullable type (https://wiki.php.net/rfc/nullable_types)
The parent change ensures that PHP 7.1+ is required.
This change reverts commit 8eb162020f.
Change-Id: Ifb8fc52f4b161ea89fef2c84e51e4c8f2b648a49