title: ExtJS 5 - Paging toolbar for Grid not working with Memory Proxy
body: <p>I am loading inline data in my store with a memory proxy and enabling paging, but the problem is that my paging toolbar only shows the first page of data. The "Next" arrow button doesn't update the grid either. I have links to images at the bottom to show what the grid panel looks like.</p>
  
  <p>This is my store:</p>
  
  <pre><code>Ext.define('PagingBug.store.MyGrid', {
      extend: 'Ext.data.Store',
      alias: 'store.mygrid',
  
      data: [
         [ 'Data1', 'Something1' ],
         [ 'Data2', 'Something2' ],
         [ 'Data3', 'Something3' ],
         [ 'Data4', 'Something4' ],
         [ 'Data5', 'Something5' ],
         [ 'Data6', 'Something6' ],
         [ 'Data7', 'Something7' ],
         [ 'Data8', 'Something8' ]
      ],
  
      fields: [
          {name: 'field1'},
          {name: 'field2'}
      ],
  
      pageSize: 5,
  
      proxy: {
          type: 'memory',
          enablePaging: true,
          reader: {
              type: 'array'
          }
      }
  });
  </code></pre>
  
  <p>This is my view:</p>
  
  <pre><code>Ext.define('PagingBug.view.main.Main', {
      extend: 'Ext.container.Container',
      requires: [
          'PagingBug.store.MyGrid'
      ],
  
      xtype: 'app-main',
  
      items: [{
          xtype: 'gridpanel',
          store: {
              type: 'mygrid'
          },
          columns: [
                  {text: 'Field 1', dataIndex: 'field1'},
                  {text: 'Field 2', dataIndex: 'field2'}
          ],
          dockedItems: [{
              xtype: 'pagingtoolbar',
              store: {
                  type: 'mygrid'
              },
              dock: 'bottom',
              displayInfo: true
          }],
      }]
  });
  </code></pre>
  
  <p>Images of the grid panel:</p>
  
  <p><a href="http://i.stack.imgur.com/PCqSC.png" rel="nofollow">http://i.stack.imgur.com/PCqSC.png</a></p>
  
  <p><a href="http://i.stack.imgur.com/S8CXU.png" rel="nofollow">http://i.stack.imgur.com/S8CXU.png</a></p>
  
  <p>Can someone please point out what I am doing wrong? Thanks.</p>