/**
  * Sends a generic command to the session. It is up to the session creator to decide what commands
  * and parameters they will support. As such, commands should only be sent to sessions that the
  * controller owns.
  *
  * @param command The command to send
  * @param params Any parameters to include with the command
  * @param cb The callback to receive the result on
  */
 public void sendCommand(String command, Bundle params, ResultReceiver cb) {
   if (TextUtils.isEmpty(command)) {
     throw new IllegalArgumentException("command cannot be null or empty");
   }
   mImpl.sendCommand(command, params, cb);
 }