Set the notification publicly visible

Signed-off-by: Dmitriy Bogdanov <d@di72nn.com>

ultrasonic/src/main/java/org/moire/ultrasonic/service/DownloadServiceImpl.java

@@ -2079,6 +2079,7 @@ public class DownloadServiceImpl extends Service implements DownloadService
         builder.setAutoCancel(false);
         builder.setOngoing(true);
         builder.setWhen(System.currentTimeMillis());
+        builder.setVisibility(NotificationCompat.VISIBILITY_PUBLIC);
 
         RemoteViews contentView = new RemoteViews(this.getPackageName(), R.layout.notification);
         Util.linkButtons(this, contentView, false);