(split) Added test on value of output stream socket pointer in APIs

src/Application.cpp

@@ -466,8 +466,10 @@ void Instance::setErrorMessage(const std::string& message) {
 }
 
 void Instance::setOutputStreamSocket(std::unique_ptr<OutputStreamSocket>& socket) {
+	if (socket) {
 		m_outputStreamSocket = std::move(socket);
 		m_outputStreamSocket->setApplicationId(m_id);
+	}
 }
 
 void Instance::setPastStates(State pastStates) {