TextEditor: Use callback in refactoring markers

Allows to trigger actions without adding specific handling into the
editor.

Change-Id: Ia63d65d3feca37bcefca1b6322ade039027a92d8
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/qmljseditor/qmljseditor.h

@@ -108,7 +108,6 @@ protected:
                     bool resolveTarget = true,
                     bool inNextSplit = false) override;
     QString foldReplacementText(const QTextBlock &block) const override;
-    void onRefactorMarkerClicked(const TextEditor::RefactorMarker &marker) override;
 
 private:
     void setSelectedElements();