BaseTextMark: Support renaming files

Change-Id: I8d712f76fca5d8f5ecad70f1485228e21c00648d
Reviewed-by: Eike Ziller <eike.ziller@nokia.com>

src/plugins/coreplugin/idocument.h

@@ -116,6 +116,7 @@ signals:
 
     void aboutToReload();
     void reloaded();
+    void fileNameChanged(const QString &oldName, const QString &newName);
 
 private:
     QString m_autoSaveName;