title: ExtJS6 TreeGrid Not Displaying Child Nodes
body: <p>I have a tree grid based on the following code:</p>
  
  <pre><code>Ext.application({
      name : 'Fiddle',
      launch : function() {
          var treeData = [{
              mtype: 'InsDataModel',
              recordid: '1',
              companyname: 'Company 1',
              children:[{           
                  mtype: 'PlnDataModel',
                  recordid: '1A',
                  planname: 'Plan 1A'
              },{
                  mtype: 'PlnDataModel',                
                  recordid: '1B',
                  planname: 'Plan 1B'
              }]
          },{
              mtype: 'InsDataModel',            
              recordid: '2',
              companyname: 'Company 2',
              children: []
          },{
              mtype: 'InsDataModel',            
              recordid: '3',
              companyname: 'Company 3',
              children:[{
                  mtype: 'PlnDataModel',                
                  recordid: '3A',
                  planname: 'Plan 3A'
              },{
                  mtype: 'PlnDataModel',                
                  recordid: '3B',
                  planname: 'Plan 3B'
              },{
                  mtype: 'PlnDataModel',                
                  recordid: '3C',
                  planname: 'Plan 3C'
              },{
                  mtype: 'PlnDataModel',                
                  recordid: '3D',
                  planname: 'Plan 3D'
              },{
                  mtype: 'PlnDataModel',                
                  recordid: '3E',
                  planname: 'Plan 3E'                
              }]
          }];
          Ext.define('InsDataModel',{
              extend: 'Ext.data.TreeModel',
              childType: 'PlnDataModel',
              fields:[
                  {name: 'recordid'},
                  {name: 'text', mapping:'companyname'}
              ]            
          });
          Ext.define('PlnDataModel',{
              extend: 'Ext.data.TreeModel',
              fields:[
                  {name: 'recordid'},
                  {name: 'text', mapping:'planname'}
              ]
          });
          Ext.define('InsDataStore',{
              extend: 'Ext.data.TreeStore',
              model: 'InsDataModel',
              proxy:{                
                  reader:{typeProperty: 'mtype'}
              },
              data:treeData,            
          });
          Ext.define('InsDataGrid',{
              extend: 'Ext.tree.Panel',
              store: {
                  model: 'InsDataModel',
                  proxy:{          
                      type: 'memory',
                      reader:{typeProperty: 'mtype'}
                  },
                  data:treeData
              },
              title: 'My tree Demo',
              renderTo: Ext.getBody(),
              width: 400,            
              height: 600,            
              useArrows: true,
              columns:[{
                  text: 'Network',
                  dataIndex: 'text',
                  flex: 1
              }]
          });               
          var newTree = Ext.create('InsDataGrid').show();
      }
  });
  </code></pre>
  
  <p>Which is also located at: <a href="https://fiddle.sencha.com/#fiddle/136t" rel="nofollow">https://fiddle.sencha.com/#fiddle/136t</a></p>
  
  <p>The problem I am running into is the child nodes will not display the text when the parent node is expanded.  Can someone please take a look at the code and let me know what I am doing incorrectly.  Thank you.</p>