Debugger: Don't reset script evaluator in QmlCppEngine

If we don't set it, we shouldn't delete it, either. The QML slave
engine will handle that.

Change-Id: Idef54e6bbb4124ed195d88a367ef07c9bb8f6b3d
Reviewed-by: hjk <hjk@theqtcompany.com>

src/plugins/debugger/qml/qmlcppengine.cpp

@@ -451,7 +451,6 @@ void QmlCppEngine::shutdownEngine()
 {
     EDEBUG("\nMASTER SHUTDOWN ENGINE");
     m_cppEngine->shutdownSlaveEngine();
-    debuggerConsole()->setScriptEvaluator(ScriptEvaluator());
 }
 
 void QmlCppEngine::quitDebugger()