QmlProfiler: Improve robustness of QmlProfilerTool test

The QmlProfilerClientManager will only report connectionClosed() if the
connection was open before it dropped. If the connection never opens,
that is the hello message never arrives, it will retry a few times,
triggering the QTRY_VERIFY timeout.

We don't want the retries to succeed, so close the server after the
first connection. Furthermore we want the hello message to be
transferred before dropping the connection, so check for isConnected().

Change-Id: Ie96c48b2aaf2748d082c4bef3efe85c261ca4812
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/qmlprofiler/tests/qmlprofilertool_test.cpp

@@ -50,6 +50,7 @@ void QmlProfilerToolTest::testAttachToWaitingApplication()
     connect(&server, &QTcpServer::newConnection, this, [&]() {
         connection.reset(server.nextPendingConnection());
         fakeDebugServer(connection.data());
+        server.close();
     });
 
     QTimer timer;
@@ -68,6 +69,7 @@ void QmlProfilerToolTest::testAttachToWaitingApplication()
 
     QTRY_VERIFY(connection);
     QTRY_VERIFY(runControl->isRunning());
+    QTRY_VERIFY(profilerTool->clientManager()->isConnected());
 
     connection.reset();
     QTRY_VERIFY(runControl->isStopped());