title: Ext.tree.Panel, itemclick, getTreeStore() not found in 5.x but works in 4.x
body: <p>this code works ok in 4.x. The goal is to open/close tree items with single click.
  In 5.x after click occurs error: "self.getTreeStore is not a function"
  I can't find the relevant change in API docs.
  Could you give me a hint why 4.x and 5.x work different?</p>
  
  <pre><code>Ext.onReady(function(){
      Ext.create('Ext.tree.Panel', {
          border: false,
          height: 200,
          listeners: { itemclick: function(self, record, item, index, event) {
                         if (record.data.href=='') {
                           var Enode=self.getTreeStore().getNodeById(record.internalId);
                           if (Enode.isExpanded()) 
                             Enode.collapse();
                           else
                             Enode.expand();
                         } } },
          rootVisible: false,
          width: 200,
          root: {
              children: [ { 
                 text: 'Menu 1',
                 children: [{ text: 'Menu 1.1',leaf: true }]
              } ] },
          renderTo: Ext.getBody()
      });
  });
  </code></pre>
  
  <p>regards,
  annie</p>