code: function() {
          Garnish.getBodyScrollTop._scrollTop = document.body.scrollTop;
  
          if (Garnish.getBodyScrollTop._scrollTop < 0) {
              Garnish.getBodyScrollTop._scrollTop = 0;
          }
          else {
              Garnish.getBodyScrollTop._maxScrollTop = Garnish.$bod.outerHeight() - Garnish.$win.height();
  
              if (Garnish.getBodyScrollTop._scrollTop > Garnish.getBodyScrollTop._maxScrollTop) {
                  Garnish.getBodyScrollTop._scrollTop = Garnish.getBodyScrollTop._maxScrollTop;
              }
          }
  
          return Garnish.getBodyScrollTop._scrollTop;
      }
docs: Returns the body's real scrollTop, discarding any window banding in Safari.
  
  @return {number}