DSVideoWidgetSurface: Pass on parent to base class.

Change-Id: If4f2819a0767234e5fffeafe1ab038cbf13bdd2a
Reviewed-by: Yoann Lopes <yoann.lopes@digia.com>

src/plugins/directshow/camera/dsvideowidgetcontrol.cpp

@@ -48,6 +48,7 @@
 QT_BEGIN_NAMESPACE
 
 DSVideoWidgetSurface::DSVideoWidgetSurface(QLabel *pWidget, QObject *parent)
+    : QAbstractVideoSurface(parent)
 {
     widget = pWidget;
     myPixmap = 0;