QMediaPlayer: The progressbar shows wrong status when play audio file for the second time.

How to reproduce:
=================================
1. Launch the qmediaplayer application.
2. Tap file icon to select a audio file to play.
3. Wait the playing finished, and tap the "Play" button to play again.

Expected result:
=================================
The progressbar should return to its original beginning position while playing finished or play again.

Actual result:
=================================
The progressbar stays at the ending position even if playing for the second time.

More detail in private JIRA: https://qtrequirements.troll.no/browse/QT-4801