title: ExtJS 4.1 - Disappearing selection when editing cell (ComboBox editor)
body: <p>I have GridPanel with 2 columns :</p>
  
  <ol>
  <li>Type : string</li>
  <li>Details : combo</li>
  </ol>
  
  <p>I added CheckBox selection model and I have a little problem.</p>
  
  <p>When I select couple rows and want to edit Details column in some of the selected row or even not-selected, selection disappears. Only edited row remain selected.
  I can't find any solution for this. Can anyone help me ?</p>
  
  <p>JSFiddle : <a href="http://jsfiddle.net/papcio28/fkJT3/6/" rel="nofollow">http://jsfiddle.net/papcio28/fkJT3/6/</a></p>