if (!msg.hasStartEventMessage() || msg.getMessageType() != PokerTHMessageType.Type_StartEventMessage) {
failOnErrorMessage(msg);
fail("Invalid message.");
}
// Acknowledge start event.
StartEventAckMessage startAck = StartEventAckMessage.newBuilder()
.setGameId(gameId)
.build();
msg = PokerTHMessage.newBuilder()
.setMessageType(PokerTHMessageType.Type_StartEventAckMessage)
.setStartEventAckMessage(startAck)