Adds a UI for accepting Discord join requests in Dolphin

also did these things
fixed crash from joining user that isn't hosting via a direct connection
current game stat can now pass to override the current game in config
uses ip endpoint from dolphin.org

Source/Core/DolphinQt/DiscordHandler.cpp

@@ -0,0 +1,81 @@
+// Copyright 2018 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#ifdef USE_DISCORD_PRESENCE
+
+#include <iterator>
+
+#include <QApplication>
+
+#include "DolphinQt/DiscordHandler.h"
+
+#include "Common/Thread.h"
+
+#include "UICommon/DiscordPresence.h"
+
+DiscordHandler::DiscordHandler(QWidget* parent) : QObject{parent}, m_parent{parent}
+{
+  connect(this, &DiscordHandler::JoinRequest, this, &DiscordHandler::ShowNewJoinRequest);
+}
+
+DiscordHandler::~DiscordHandler()
+{
+  Stop();
+}
+
+void DiscordHandler::Start()
+{
+  m_stop_requested.Set(false);
+  m_thread = std::thread(&DiscordHandler::Run, this);
+}
+
+void DiscordHandler::Stop()
+{
+  m_stop_requested.Set(true);
+
+  if (m_thread.joinable())
+    m_thread.join();
+}
+
+void DiscordHandler::DiscordJoinRequest(const char* id, const std::string& discord_tag,
+                                        const char* avatar)
+{
+  m_request_dialogs.emplace_front(m_parent, id, discord_tag, avatar);
+  emit DiscordHandler::JoinRequest();
+}
+
+void DiscordHandler::DiscordJoin()
+{
+  emit DiscordHandler::Join();
+}
+
+void DiscordHandler::ShowNewJoinRequest()
+{
+  m_request_dialogs.front().show();
+  QApplication::alert(nullptr, DiscordJoinRequestDialog::s_max_lifetime_seconds * 1000);
+}
+
+void DiscordHandler::Run()
+{
+  while (!m_stop_requested.IsSet())
+  {
+    if (m_thread.joinable())
+      Discord::CallPendingCallbacks();
+
+    // close and remove dead requests
+    for (auto request_dialog = m_request_dialogs.rbegin();
+         request_dialog != m_request_dialogs.rend(); ++request_dialog)
+    {
+      if (std::time(nullptr) < request_dialog->GetCloseTimestamp())
+        continue;
+      request_dialog->close();
+      std::advance(request_dialog, 1);
+      m_request_dialogs.erase(request_dialog.base());
+    }
+
+    Common::SleepCurrentThread(1000 * 2);
+  }
+}
+
+#endif