QMediaPlayer: "Exit" button doesn't work after finishing play video in fullscreen mode.

How to reproduce:
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1. Launch the qmediaplayer application.
2. Tap file icon to select a .mp4 file to play.
3. While video is playing, tap file icon to check "Full screen video".

Expected result:
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Video should play normally in full screen mode.

Actual result:
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After playing finished, can't quit the application with the "exit" button.

More detail in private JIRA: https://qtrequirements.troll.no/browse/QT-4798