DebuggerEngine: fixed race condition at qml engine startup

Reviewed by: hjk

src/plugins/debugger/qml/qmlcppengine.cpp

@@ -449,7 +449,7 @@ void QmlCppEngine::finishDebugger()
 
 void QmlCppEngine::setupSlaveEngineOnTimer()
 {
-    QTimer::singleShot(ConnectionWaitTimeMs, this, SLOT(setupSlaveEngine()));
+    QTimer::singleShot(0, this, SLOT(setupSlaveEngine()));
 }
 
 void QmlCppEngine::setupSlaveEngine()

src/plugins/debugger/qml/qmlengine.cpp

@@ -260,9 +260,13 @@ void QmlEngine::shutdownInferiorAsSlave()
     if (state() == InferiorRunOk) {
         setState(InferiorStopRequested);
         setState(InferiorStopOk);
+        setState(InferiorShutdownRequested);
+        setState(InferiorShutdownOk);
+    } else {
+        // force
+        setState(InferiorShutdownRequested, true);
+        setState(InferiorShutdownOk);
     }
-    setState(InferiorShutdownRequested);
-    setState(InferiorShutdownOk);
 }
 
 void QmlEngine::shutdownEngineAsSlave()