title: Quick filter in datasheet is missing
body: <p>I have a subform in datasheet view mode and it has missing the filter option that generally appear with checkboxes.  </p>
  
  <p>Missing<br>
  <img src="https://content.screencast.com/users/AmitKB/folders/Jing/media/a78f4a15-d191-493b-ab32-078361a5e42e/2012-08-21_1210.png" alt="">  </p>
  
  <p>By qick filter and checkboxes for filter I mean this:<br>
  <img src="https://content.screencast.com/users/AmitKB/folders/Jing/media/88cbd164-d55d-46b5-87e2-fbff86f8dbf1/2012-08-21_1209.png" alt=""> </p>
  
  <p>Can somebody tell me how can I get that back?</p>