code: function (ownerContext, axis) {
          var size = axis.end - axis.begin,
              center = ownerContext.centerRegion;
  
          if (center) {
              center['set' + axis.sizePropCap](size - center.getMarginInfo()[axis.sizeProp]);
              center.layoutPos[axis.posProp] = axis.begin;
          }
  
          return Ext.isNumber(size) ? 1 : 0;
      }
docs: Finishes the calculations on an axis. This basically just assigns the remaining
  space to the center region.
  @private