Test for activation and palette on QWindowContainer's parent

Task-number: QTBUG-31775

Change-Id: Ib8ec5508f7bf53f9e3ce502367a3dca1a760289f
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>
Fix QWidget::isActiveWindow for window containers.

Change-Id: If0e8b83d7dc84b66f4ce5a5cd98affa4bd9b7424
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>