title: Vbox container doesn't resize after add function. Extjs4
body: <p>I'm trying to dynamically add a component to a container with the hbox layout specified
  and have that container re-size itself to accommodate the new component. Currently the 
  new component is added, but the new and old components are re-sized / or tiled in the
  container and the container maintains its size.</p>
  
  <p>Here is a demonstration of the issue I'm having on <a href="http://jsfiddle.net/qrCE9/" rel="nofollow">jsfiddle</a>.</p>
  
  <p>Here is the relevant extjs4 javascript for the demo:</p>
  
  <pre><code>Ext.onReady(function(){
  Ext.create ('Ext.panel.Panel', {
      title: 'test',
      width: 300,
      height: 300,
      items: [
          {
              xtype: 'container',
              layout: 'hbox',
              padding : 5,
              items: [
                  {
                      xtype: 'container',
                      id: 'textfieldgroup',
                      flex: 1,
                      height: '100%',
                      border: false,
                      layout: {
                          type: 'vbox',
                      },
                      defaults: {
                          flex: 1,
                      },
                      items: [
                          {
                              xtype: 'textfield',
                              emptyText: 'type here',
                          },
                      ],
  
                  },
                  {
                      xtype: 'button',
                      flex: .1,
                      text: '+',
                      listeners: {
                          'click' : function () {
                              var textFieldGroup = 
                                  Ext.ComponentQuery.query ('#textfieldgroup')[0];
                              var newTextField = Ext.widget ('textfield');
                              textFieldGroup.add (newTextField);
                          },                        
                      }
                  }                        
              ]
          }                
      ],
      renderTo: Ext.getBody ()        
  });
  </code></pre>
  
  <p>});</p>