QmlProfiler: stop trying to connect when the application quits

Change-Id: I3b33ced218320a19fd4e4e834093c0f3b67a8cba
Task-number: QTCREATORBUG-20499
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/libs/qmldebug/qmldebugconnectionmanager.cpp

@@ -71,6 +71,11 @@ void QmlDebugConnectionManager::disconnectFromServer()
     stopConnectionTimer();
 }
 
+bool QmlDebugConnectionManager::isConnecting() const
+{
+    return m_connectionTimer.isActive();
+}
+
 static quint16 port16(const QUrl &url)
 {
     const int port32 = url.port();