Clean code

app/src/main/java/com/fongmi/android/tv/bean/Track.java

@@ -106,7 +106,7 @@ public class Track {
     }
 
     public boolean isIjk(int player) {
-        return getPlayer() == player && player != Players.EXO;
+        return getPlayer() == player && (player == Players.IJK || player == Players.SYS);
     }
 
     public Track toggle() {

app/src/main/java/com/fongmi/android/tv/player/Players.java

@@ -608,7 +608,7 @@ public class Players implements Player.Listener, IMediaPlayer.Listener, ParseCal
     }
 
     private List<Sub> checkSub(List<Sub> subs) {
-        if (sub == null) return new ArrayList<>();
+        if (sub == null) return subs;
         subs.add(0, sub);
         return subs;
     }