code: function(scrollX, scrollY) {
          var dimensionModel = this.dimensionModel;
          var summaryHeight = dimensionModel.get('summaryHeight');
          var summaryPosition = dimensionModel.get('summaryPosition');
          var topHeight = dimensionModel.get('headerHeight');
          var bottomHeight = scrollX ? dimensionConst.SCROLLBAR_WIDTH : 0;
  
          if (scrollY && summaryHeight) {
              if (summaryPosition === summaryPositionConst.TOP) {
                  topHeight += summaryHeight + dimensionConst.TABLE_BORDER_WIDTH;
              } else {
                  bottomHeight += summaryHeight;
              }
          }
  
          return {
              top: topHeight,
              bottom: bottomHeight
          };
      }
docs: Get height values of top, bottom space on scroll area
  @param {boolean} scrollX - Whether the grid has x-scroll or not
  @param {boolean} scrollY - Whether the grid has y-scroll or not
  @returns {object} Heighs value
  @private