title: ExtJS 4 RowEditing disable edit on one column based on record
body: <p>I'm implementing a grid panel with the four last columns editable for most of the rows. The problem is that I'd like to be able to disable editing on, let's say the first one if record.get('status') = 4 which is finalized and only two of the columns should be editable.</p>
  
  <p>Is there a way to disable showing the edit for those rows? I can do it using CellEditing but want to keep using the RowEditing plugin.</p>
  
  <p>Regards,
  Kristian</p>