Improve thread safety.

src/net/common/clientstate.cpp

@@ -1732,6 +1732,9 @@ ClientStateWaitHand::InternalHandlePacket(boost::shared_ptr<ClientThread> client
 			cardDataStream >> myCards[0];
 			cardDataStream >> myCards[1];
 		}
+		// Basic synchronisation before a new hand is started.
+		client->GetGui().waitForGuiUpdateDone();
+		// Start new hand.
 		client->GetGame()->getSeatsList()->front()->setMyCards(myCards);
 		client->GetGame()->initHand();
 		client->GetGame()->getCurrentHand()->setSmallBlind(netHandStart->smallBlind);

src/net/common/clientthread.cpp

@@ -1219,7 +1219,7 @@ void
 ClientThread::RemoveDisconnectedPlayers()
 {
 	// This should only be called between hands.
-	if (m_game.get())
+	if (m_game)
 	{
 		PlayerListIterator it;
 		for (it = m_game->getSeatsList()->begin(); it != m_game->getSeatsList()->end(); it++)