Fix entity tracking when the player is the vehicle

Fixes GH-378

Spigot-Server-Patches/Entity-Tracking-Improvements.patch

@@ -73,7 +73,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +        return false;
 +    }
 +    private static boolean isTrackedBy(Entity entity, EntityPlayer entityplayer) {
-+        return entity.tracker != null && entity.tracker.trackedPlayers.contains(entityplayer);
++        return entity == entityplayer || entity.tracker != null && entity.tracker.trackedPlayers.contains(entityplayer);
 +    }
 +    private void updatePassengers(EntityPlayer player) {
 +        if (tracker.isVehicle()) {