Extjs remember grid state in cookies

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<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>Remember grid state</title>
    <link rel="stylesheet" type="text/css" href="library/ext/ext-3.3.0/resources/css/ext-all.css" />
    <script type="text/javascript" src="library/ext/ext-3.3.0/adapter/ext/ext-base.js"></script>
    <script type="text/javascript" src="library/ext/ext-3.3.0/ext-all.js"></script>
    <!-- STATE PROVIDER VIA COOKIES -->
    <script type="text/javascript">
      Ext.state.Manager.setProvider(
        new Ext.state.CookieProvider({
          expires: new Date(new Date().getTime() + 1000 * 60 * 60 * 24 * 7) //7 days from now
        })
      )
    </script>
    <!-- LOCAL DATA -->
    <script type="text/javascript">
      var myData = [
        ['3m Co', 71.72, 0.02, 0.03, '9/1 12:00am'],
        ['Alcoa Inc', 29.01, 0.42, 1.47, '9/1 12:00am'],
        ['Altria Group Inc', 83.81, 0.28, 0.34, '9/1 12:00am'],
        ['American Express Company', 52.55, 0.01, 0.02, '9/1 12:00am'],
        ['American International Group, Inc.', 64.13, 0.31, 0.49, '9/1 12:00am'],
        ['AT&T Inc.', 31.61, -0.48, -1.54, '9/1 12:00am'],
        ['Boeing Co.', 75.43, 0.53, 0.71, '9/1 12:00am'],
        ['Caterpillar Inc.', 67.27, 0.92, 1.39, '9/1 12:00am'],
        ['Citigroup, Inc.', 49.37, 0.02, 0.04, '9/1 12:00am'],
        ['E.I. du Pont de Nemours and Company', 40.48, 0.51, 1.28, '9/1 12:00am'],
        ['Exxon Mobil Corp', 68.1, -0.43, -0.64, '9/1 12:00am'],
        ['General Electric Company', 34.14, -0.08, -0.23, '9/1 12:00am'],
        ['General Motors Corporation', 30.27, 1.09, 3.74, '9/1 12:00am'],
        ['Hewlett-Packard Co.', 36.53, -0.03, -0.08, '9/1 12:00am'],
        ['Honeywell Intl Inc', 38.77, 0.05, 0.13, '9/1 12:00am'],
        ['Intel Corporation', 19.88, 0.31, 1.58, '9/1 12:00am'],
        ['International Business Machines', 81.41, 0.44, 0.54, '9/1 12:00am'],
        ['Johnson & Johnson', 64.72, 0.06, 0.09, '9/1 12:00am'],
        ['JP Morgan & Chase & Co', 45.73, 0.07, 0.15, '9/1 12:00am'],
        ["McDonald's Corporation", 36.76, 0.86, 2.4, '9/1 12:00am'],
        ['Merck & Co., Inc.', 40.96, 0.41, 1.01, '9/1 12:00am'],
        ['Microsoft Corporation', 25.84, 0.14, 0.54, '9/1 12:00am'],
        ['Pfizer Inc', 27.96, 0.4, 1.45, '9/1 12:00am'],
        ['The Coca-Cola Company', 45.07, 0.26, 0.58, '9/1 12:00am'],
        ['The Home Depot, Inc.', 34.64, 0.35, 1.02, '9/1 12:00am'],
        ['The Procter & Gamble Company', 61.91, 0.01, 0.02, '9/1 12:00am'],
        ['United Technologies Corporation', 63.26, 0.55, 0.88, '9/1 12:00am'],
        ['Verizon Communications', 35.57, 0.39, 1.11, '9/1 12:00am'],
        ['Wal-Mart Stores, Inc.', 45.45, 0.73, 1.63, '9/1 12:00am']
      ]
    </script>
    <!-- STORE -->
    <script type="text/javascript">
      var store = new Ext.data.ArrayStore({
        fields: [
          { name: 'company' },
          { name: 'price', type: 'float' },
          { name: 'change', type: 'float' },
          { name: 'pctChange', type: 'float' },
          { name: 'lastChange', type: 'date', dateFormat: 'n/j h:ia' }
        ]
      })
      store.loadData(myData)
    </script>
    <!-- GRID -->
    <script type="text/javascript">
      var grid = new Ext.grid.GridPanel({
        id: 'grid', //need for state
        region: 'center',
        viewConfig: { forceFit: true },
        store: store,
        colModel: new Ext.grid.ColumnModel({
          defaults: { sortable: true },
          columns: [
            //do not forget about column ids
            { dataIndex: 'company', id: 'company', header: 'Company' },
            { dataIndex: 'price', id: 'price', header: 'Price' },
            { dataIndex: 'change', id: 'change', header: 'Change' },
            { dataIndex: 'pctChange', id: 'pctChange', header: '% Change' },
            { dataIndex: 'lastChange', id: 'lastChange', header: 'Last Updated' }
          ]
        }),
        stateful: true //enable rememebering state
      })
    </script>
    <!-- ON PAGE LOAD -->
    <script type="text/javascript">
      Ext.onReady(function () {
        Ext.QuickTips.init()

        new Ext.Viewport({
          layout: 'border',
          items: [grid]
        })
      })
    </script>
  </head>
  <body></body>
</html>