[TASK] Update to phpunit 4.1

Do not forget to "composer update" test instances!

Updating from phpunit 3.7 to 4.1 is smooth, except two details:

* The mock framework dropped staticExpects, two test cases must
  be refactored to circumvent this.

* The mocker now tries to resolve method argument type hints, so
  those classes must exist and autoloaded, some FLOW dependencies
  are affected here.

Change-Id: Ie74bdad000182dde808d3771fa6eec4764a133da
Resolves: #58676
Releases: 6.2