title: How to fit gridPanels columns?
body: <p>I have application using ExtJs 3.4.<br>
  I have this construction:</p>
  
  <p>westPanel-TabPanel:</p>
  
  <pre><code>var westPanel = new Ext.TabPanel({
              id: "west",
              //xtype: "tabpanel",
              //layout:'fit',
              activeTab: 0,
              region: "west",
              border: false,
              width: 278,
              split: true,
              collapseMode: "mini",
              items: [mapList,structure,cadastr,search]
          });
  </code></pre>
  
  <p>Search - FormPanel:</p>
  
  <pre><code>var search = new Ext.FormPanel({
                  labelAlign: 'top',
                  frame:true,
                  title: 'Поиск',
                  bodyStyle:'padding:5px 5px 0',
                  //width: 600,
                  //layout:'fit',
                  items: [{
                      xtype:'textfield',
                      fieldLabel: 'Диспечерское наименование',
                      name: 'name_dispather',
                      anchor:'100%',
                      enableKeyEvents: true,
                      listeners: {
                          'keyup': function(e) {
                              if(e.getValue().length==4){
                                  searchStore.load({params:{'name':e.getValue()}});
                              }
                          }
                      }
                  },searchTab]
              });
  </code></pre>
  
  <p>SearchTab - GridPanel:</p>
  
  <pre><code>var searchTab = new Ext.ux.grid.livegrid.GridPanel({
      store: searchStore,
      region: 'center',
      cm: searchCm, 
      layout: 'fit',
      selModel: new Ext.ux.grid.livegrid.RowSelectionModel(),
      stripeRows : true,
      view: myView,
      height: 390,
      loadMask: true,
      id: 'searchTab',
      title:'Найденные объекты',
      autoScroll: true,
  });
  </code></pre>
  
  <p>And i have a problem:</p>
  
  <p><img src="https://i.stack.imgur.com/DZ6fJ.jpg" alt="enter image description here">               </p>
  
  <p>Have to make last column's width to whole panel's width?</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>I try autoExpandColumn. its works but its not idial:</p>
  
  <p><img src="https://i.stack.imgur.com/mjj1m.jpg" alt="enter image description here"></p>
  
  <p>How to fix it?</p>