title: Ext.data.Store getTotalCount() doesn't calculate after load
body: <p>My store doesn't always return the right amount of records when calling <code>getTotalCount()</code>. This problem occurs after I <code>load()</code> the store. I know that there are records in the store at that point of checking.<br>
  I am using ExtJs 4.1.3</p>
  
  <pre><code>//this.grid = reference to my grid
  var count = this.grid.getStore().getCount(), //50
      total = this.grid.getStore().getTotalCount(); //16000
  
      this.grid.getStore().load();
  
      count = this.grid.getStore().getCount(); //50
      total = this.grid.getStore().getTotalCount(); //0
  </code></pre>
  
  <p><strong>How can I get the number of records that could be loaded into the Store if the Store contained all data?</strong></p>
  
  <hr>
  
  <p>My store configuration.</p>
  
  <pre><code>store: Ext.create('Ext.data.Store', {
                  model: me.modelName,
                  remoteSort: true,
                  remoteFilter: true,
                  pageSize: 50,
                  trailingBufferZone: 25,
                  leadingBufferZone: 50,
                  buffered: true,
                  proxy: {
                      type: 'ajax',
                      actionMethods: { read: 'POST' },
                      api: {
                          read: me.urls.gridUrl
                      },
                      extraParams: Ext.applyIf({ FilterType: 0 }, me.urlParams.gridUrlParams),
                      simpleSortMode: true,
                      reader: {
                          type: 'json',
                          root: 'data',
                          totalProperty: 'total'
                      }
                  },
                  autoLoad: true
              })
  </code></pre>
  
  <p>I can confirm that the <code>total</code> property is send for all of my requests.</p>
  
  <pre><code>{
      "succes": true,
      "data": [
      //50 records
      ],
      "total": 16219,
      "errors": []
  }
  </code></pre>