QMediaPlayer does not emit "error" signal for invalid file on mac (av foundation)

When you try to load a bogus or unsupported media file there is no indication of this error. I believe the problem lies in the fact the av foundation impl (qtmultimedia/src/plugins/avfoundation/mediaplayer/avfmediaplayersession.mm) does not emit this signal when it has an error. There is a TODO in there that I believe should emit the "error" signal.

Code below would probably be sufficient.

-(void) assetFailedToPrepareForPlayback:(NSError *)error
{
Q_UNUSED(error)
//TODO: Let the session know that the assest failed to prepare for playback

// Let the media player know that something went wrong
Q_EMIT error(QMediaPlayer::FormatError, tr("Failed to load media"));

#ifdef QT_DEBUG_AVF
qDebug() << Q_FUNC_INFO;
qDebug() << [[error localizedDescription] UTF8String];
qDebug() << [[error localizedFailureReason] UTF8String];
qDebug() << [[error localizedRecoverySuggestion] UTF8String];
#endif
}