GStreamer: Fix position value at EndOfMedia

Return the duration when we're at the EndOfMedia

Task-number: QTBUG-59604
Change-Id: If057257a65d73aa456dd7dc52b6cb624dd4712d3
Reviewed-by: Yoann Lopes <yoann.lopes@qt.io>

src/plugins/gstreamer/mediaplayer/qgstreamerplayercontrol.cpp

@@ -119,6 +119,9 @@ QMediaPlayerResourceSetInterface* QGstreamerPlayerControl::resources() const
 
 qint64 QGstreamerPlayerControl::position() const
 {
+    if (m_mediaStatus == QMediaPlayer::EndOfMedia)
+        return m_session->duration();
+
     return m_pendingSeekPosition != -1 ? m_pendingSeekPosition : m_session->position();
 }