remove obscure comment

Task-number: QTBUG-73826
Change-Id: I2d15ab726ae3be85220bf96aef673d0037738d97
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

src/gui/kernel/qguiapplication.cpp

@@ -2187,8 +2187,6 @@ void QGuiApplicationPrivate::processWheelEvent(QWindowSystemInterfacePrivate::Wh
 #endif // QT_CONFIG(wheelevent)
 }
 
-// Remember, Qt convention is:  keyboard state is state *before*
-
 void QGuiApplicationPrivate::processKeyEvent(QWindowSystemInterfacePrivate::KeyEvent *e)
 {
     QWindow *window = e->window.data();