Hooked up the QML task manager again.

The QML task manager behaviour is to show warnings/errors for _saved_ files
only.

src/plugins/qmljseditor/qmljseditor.h

@@ -218,6 +218,7 @@ public slots:
 
 private slots:
     void onDocumentUpdated(QmlJS::Document::Ptr doc);
+    void modificationChanged(bool);
 
     void updateDocument();
     void updateDocumentNow();