ProjectExplorer: Fix the "unload while building" case

This probably broke in or around 966f4ea6a9.

Change-Id: Ib61f181558b0ebeb17d6b52798af80b7307cac41
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/projectexplorer/buildmanager.cpp

@@ -700,8 +700,7 @@ void BuildManager::nextStep()
             disconnect(d->m_currentBuildStep, nullptr, instance(), nullptr);
             BuildManager::nextBuildQueue();
         };
-        connect(d->m_currentBuildStep, &BuildStep::finished, instance(), finishedHandler,
+        connect(d->m_currentBuildStep, &BuildStep::finished, instance(), finishedHandler);
-                Qt::QueuedConnection);
         connect(d->m_currentBuildStep, &BuildStep::progress,
                 instance(), &BuildManager::progressChanged);
         d->m_outputWindow->outputFormatter()->reset();

src/plugins/projectexplorer/buildstep.cpp

@@ -134,6 +134,11 @@ BuildStep::BuildStep(BuildStepList *bsl, Core::Id id) :
     QTC_CHECK(bsl->target() && bsl->target() == this->target());
 }
 
+BuildStep::~BuildStep()
+{
+    emit finished(false);
+}
+
 void BuildStep::run()
 {
     m_cancelFlag = false;

src/plugins/projectexplorer/buildstep.h

@@ -68,6 +68,7 @@ protected:
     explicit BuildStep(BuildStepList *bsl, Core::Id id);
 
 public:
+    ~BuildStep() override;
     virtual bool init() = 0;
     void run();
     void cancel();