QmlProfiler: fix potential crash

fixes Ib2ea66bd5694046577a0b5a0e2f611f3ffba0238

Change-Id: Ib7a4e02391513984f1c81a43a5fab490b7f88923
Reviewed-by: Kai Koehne <kai.koehne@digia.com>
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

src/plugins/qmlprofiler/localqmlprofilerrunner.cpp

@@ -41,6 +41,11 @@ LocalQmlProfilerRunner::LocalQmlProfilerRunner(const Configuration &configuratio
             this, SIGNAL(appendMessage(QString,Utils::OutputFormat)));
 }
 
+LocalQmlProfilerRunner::~LocalQmlProfilerRunner()
+{
+    disconnect();
+}
+
 void LocalQmlProfilerRunner::start()
 {
     QString arguments = QString::fromLatin1("-qmljsdebugger=port:%1,block").arg(m_configuration.port);