Add Discord Join Net Play functionally

Source/Core/DolphinQt2/DiscordHandler.h

@@ -0,0 +1,30 @@
+// Copyright 2018 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <thread>
+
+#include <QObject>
+
+#include "Common/Flag.h"
+
+class DiscordHandler : public QObject
+{
+  Q_OBJECT
+public:
+  explicit DiscordHandler();
+  ~DiscordHandler();
+
+  void Start();
+  void Stop();
+  void DiscordJoin();
+signals:
+  void Join();
+
+private:
+  void Run();
+  Common::Flag m_stop_requested;
+  std::thread m_thread;
+};