code: function(store, columns) {
          var me = this,
              oldStore = me.store,
              lockedGrid = me.lockedGrid,
              normalGrid = me.normalGrid;
  
          Ext.suspendLayouts();
          if (columns) {
              lockedGrid.headerCt.removeAll();
              normalGrid.headerCt.removeAll();
  
              columns = me.processColumns(columns);
  
              // Flag to the locked column add listener to do nothing
              me.ignoreAddLockedColumn = true;
              lockedGrid.headerCt.add(columns.locked.items);
              me.ignoreAddLockedColumn = false;
              normalGrid.headerCt.add(columns.normal.items);
  
              // Ensure locked grid is set up correctly with correct width and bottom border,
              // and that both grids' visibility and scrollability status is correct
              me.syncLockedWidth();
          }
  
          if (store && store !== oldStore) {
              store = Ext.data.StoreManager.lookup(store);
              me.store = store;
              lockedGrid.bindStore(store);
              normalGrid.bindStore(store);
          } else {
              lockedGrid.getView().refresh();
              normalGrid.getView().refresh();
          }
          Ext.resumeLayouts(true);
      }
docs: we want to totally override the reconfigure behaviour here, since we're creating 2 sub-grids