Use QVideoGraphicsItem in the videographicsitem example.

The videographicsitem example now uses QVideoGraphicsItem instead of a
custom QAbstractVideoSurface.
The old code has been moved to a new example:
"customvideosurface/customvideoitem".

Change-Id: I83212f36168ef94d670b447eb1a742a39753939d
Reviewed-by: Jason Barron <jason.barron@digia.com>

examples/videographicsitem/videoplayer.h

@@ -49,11 +49,9 @@
 QT_BEGIN_NAMESPACE
 class QAbstractButton;
 class QSlider;
+class QGraphicsVideoItem;
 QT_END_NAMESPACE
 
-
-class VideoItem;
-
 class VideoPlayer : public QWidget
 {
     Q_OBJECT
@@ -76,7 +74,7 @@ private slots:
 
 private:
     QMediaPlayer mediaPlayer;
-    VideoItem *videoItem;
+    QGraphicsVideoItem *videoItem;
     QAbstractButton *playButton;
     QSlider *positionSlider;
 };