Steps to reproduce the issue

Use patchtester latest staging.
Fetch data.
Try to Apply a patch.

Expected result

Patch applied.

Actual result

Catchable fatal error: Argument 1 passed to JModelDatabase::__construct() must be an instance of Joomla\Registry\Registry, string given, called in /path/to/joomla/administrator/components/com_patchtester/PatchTester/Controller/ApplyController.php on line 31 and defined in /path/to/joomla/libraries/joomla/model/database.php on line 37

System information (as much as possible)

PHP 5.6.18
Joomla 3.5.0 latest staging.

Additional comments

None.