title: Update model of a grid store on the fly
body: <p>A grid is configured with a store that use a model that I can call modelA</p>
  
  <p>I need to change on the fly the model of the store related to the grid.
  I followed following approach without results:</p>
  
  <pre><code>grid.getStore().setModel(modelB);
  
  grid.reconfigure(
      grid.getStore(),
      columns
  );
  
  grid.getStore().load();
  </code></pre>
  
  <p>It continues to use the model defined at the beginning. In fact if I debug the record that is passed to the renderer function as follows:</p>
  
  <pre><code>function(value, metadata, record)...
  </code></pre>
  
  <p>record continues to reference modelA instead of modelB.</p>
  
  <p>How can I change dynamically the model of the store?</p>