title: reloading store deletes filters
body: <p>I have a trigger-form-field which I use as a searchfield. Everytime the value changes, another search is performed. So far so good. But I have a PHP script which needs to be rerun every 30 seconds. For this I defined the following code in my </p>
  
  <p><strong>grid.js</strong></p>
  
  <pre><code>setInterval(function() {
              var grid = Ext.getCmp('grid');
              var store = grid.getStore();
              store.load();
          }, 30000);
  </code></pre>
  
  <p>All this works just as expected, but every time my store is reloaded, my view and filters are gone. For example:</p>
  
  <p>When I'm typing "test" in my searchfield, the grid is filtered correctly. But after refreshing the grid, the filter is not re-applied. I'd also like to keep the users view instead of being directed to the top of the page. Is that even possible?
  Thanks for any help in advance.</p>
  
  <p>I'm using ExtJS 4.2 if that matters</p>