setCornerWidget with QMenu in QWorkspace

In qt3 when we want to add a widget in qmenubar we used:
QLabel *p_label = new QLabel( this);
p_label->setPixmap( QPixmap::fromMimeSource( "logofv60.png"));
_p_menubar->insertItem( p_label, -1, 0);

But in qt4 we can't.
So I tried to use setCornerWidget
QLabel *p_label = new QLabel( this);
p_label->setPixmap( QPixmap( ":/icon/logofv60.png"));
_p_menubar->setCornerWidget( p_label, Qt::TopLeftCorner);

which is not supported and doesn't work with a QWorkspace.

So I created a patch to fix this pb.

I added patch and test case.