qmediaplayer: show buffer status of 0%

During progressive download, it is not possible for the Symbian MMF Phonon
backend to determine the buffering status, so it returns a value of 0%.

This change causes qmediaplayer to display this value in the UI, thereby
giving a visible notification of buffering during progressive download.

Task-number: QTBUG-10769
Reviewed-by: Derick Hawcroft

Author: Gareth Stockwell

demos/qmediaplayer/mediaplayer.cpp

@@ -716,7 +716,7 @@ void MediaPlayer::openFile()
 
 void MediaPlayer::bufferStatus(int percent)
 {
-    if (percent == 0 || percent == 100)
+    if (percent == 100)
         progressLabel->setText(QString());
     else {
         QString str = QString::fromLatin1("(%1%)").arg(percent);