title: Strange behavior of QFileSystemModel::filepath
body: <p>I've made selection on QFileSystemModel and now I'm trying to get those paths selected by doing:  </p>
  
  <pre><code> QList&lt;QModelIndex&gt; r = sel_model_-&gt;selectedIndexes();
      QStringList result;
  
      for (int i = 0; i &lt; r.size() ; i += 4)//four number of columns
      {
    //model_ is QFileSystemModel
          auto path = model_-&gt;filePath(r.at(i));
  
          result.append(model_-&gt;filePath(r.at(i)));
      }  
  </code></pre>
  
  <p>But the results here does not reflect my choice. If I select let's say drive D, file on drive C and another file in a folder on C, after iteration I'm getting:<br>
  result == "D", "D", "someFile on c".<br>
  Why is "D" picked for the second time?</p>