title: .down() or .query() won't find the child if it's xtype:field`s component
body: <p>At the very bottom of this short function you can see that I'm trying to get all <code>xtype: button</code> within the <code>webClip</code>. For some reason it ommits the 57x57 button and shows only remove button from the <code>titlebar</code>. I can't figure out why. This <code>xtype: field</code>'s <code>component</code> config is rather confusing for me. Thanks!</p>
  
  <pre><code>function addWebClip(type) {
  
      var webClip = Ext.create('Ext.form.FieldSet', {
  
          cls: 'webclip-title',
  
          items: [{
              xtype: 'titlebar',
              title: type + ' webclip',
  
  
              items: [{
                  text: 'remove',
                  ui: 'decline',
                  align: 'right',
  
  
                  handler: function () {
                      console.log(this.hasParent()); // TRUE
                      Ext.getCmp('main-panel').remove(this.up('fieldset'));
                  }
              }]
          }, {
              xtype: 'field',
              label: 'Icon',
              cls: 'icon-input',
  
              component: {
                  xtype: 'button',
                  width: 57,
                  height: 57,
                  iconCls: 'add1',
                  iconMask: true,
                  handler: function () {
                      var gallery = Ext.getCmp('images-gallery');
                      if (!gallery) {
                          gallery = Ext.Viewport.add({
                              xtype: 'gallery',
                              id: 'images-gallery'
                          });
                      }
                      console.log(this.hasParent()); // FALSE
  
                      gallery.setIconButton(this);
                      gallery.show();
                  }
              }
          }, {
              xtype: 'textfield',
              name: 'webClipImage[]',
              label: 'webClipImage'
          }]
      });
  
      console.log(webClip);
      console.log(webClip.query('.button'));
      Ext.getCmp('main-panel').add(webClip);
  }
  </code></pre>
  
  <p>Console.log results:</p>
  
  <pre><code>Class {items: Class, _items: Class, innerItems: Array[9], onInitializedListeners: Array[0], initialConfig: Object…}
  
  [Class]
  &gt; 0: Class
  &gt; length: 1
  &gt; __proto__: Array[0]
  </code></pre>