Removed NULL assignement for username parameter (#1429)

* Removed NULL assignement for username parameter

* Updated unit test

* More codestyle fixes

* Codestyle fixes

tests/PHPUnit/ArrayHasSameValuesConstraint.php

@@ -13,7 +13,7 @@
 /**
  * PHPUnit constraint matching arrays with same elements even in different order.
  */
-class ArrayHasSameValuesConstraint extends \PHPUnit\Framework\Constraint\Constraint
+class ArrayHasSameValuesConstraint extends PHPUnit\Framework\Constraint\Constraint
 {
     protected $array;