QWidget::mousePressEvent() closes the widget if the position is
not within the rect. A subsequent call to update() amounts to
accessing potentially corrupt memory. Hence call update() before
calling QWidget::mousePressEvent().

Change-Id: I850471d3a1dfdb0a4f0541a69fd2f239dbf8b5fa
Reviewed-by: Kai Koehne <kai.koehne@nokia.com>