add back IXWebSocketMessageQueue, with its unittest disabled

ixwebsocket/IXWebSocketMessageQueue.h

@@ -0,0 +1,53 @@
+/*
+ *  IXWebSocketMessageQueue.h
+ *  Author: Korchynskyi Dmytro
+ *  Copyright (c) 2017-2019 Machine Zone, Inc. All rights reserved.
+ */
+
+#pragma once
+
+#include "IXWebSocket.h"
+#include <thread>
+#include <list>
+#include <memory>
+
+namespace ix
+{
+    //
+    // A helper class to dispatch websocket message callbacks in your thread.
+    //
+    class WebSocketMessageQueue
+    {
+    public:
+        WebSocketMessageQueue(WebSocket* websocket = nullptr);
+        ~WebSocketMessageQueue();
+
+        void bindWebsocket(WebSocket* websocket);
+
+        void setOnMessageCallback(const OnMessageCallback& callback);
+        void setOnMessageCallback(OnMessageCallback&& callback);
+
+        void poll(int count = 512);
+
+    protected:
+        struct Message
+        {
+            WebSocketMessageType type;
+            std::string str;
+            size_t wireSize;
+            WebSocketErrorInfo errorInfo;
+            WebSocketOpenInfo openInfo;
+            WebSocketCloseInfo closeInfo;
+        };
+
+        using MessagePtr = std::shared_ptr<Message>;
+
+        MessagePtr popMessage();
+
+    private:
+        WebSocket* _websocket = nullptr;
+        OnMessageCallback _onMessageUserCallback;
+        std::mutex _messagesMutex;
+        std::list<MessagePtr> _messages;
+    };
+}