Add unit test to verify detection.

Change-Id: I2d927552ebfaf8b35b9c1cae3b65603f63c7a8c5
Reviewed-on: http://codereview.qt.nokia.com/1447


Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Eike Ziller <eike.ziller@nokia.com>