code: function Scrollbar (pane) {
        this.pane = pane;
        this.pane.el.append(this.el);
        this.innerEl = this.pane.inner.get(0);
  
        this.dragging = false;
        this.enter = false;
        this.shown = false;
  
        // hovering
        this.pane.el.mouseenter($.proxy(this, 'mouseenter'));
        this.pane.el.mouseleave($.proxy(this, 'mouseleave'));
  
        // dragging
        this.el.mousedown($.proxy(this, 'mousedown'));
  
        // scrolling
        this.innerPaneScrollListener = $.proxy(this, 'scroll');
        this.pane.inner.scroll(this.innerPaneScrollListener);
  
        // wheel -optional-
        this.innerPaneMouseWheelListener = $.proxy(this, 'mousewheel');
        this.pane.inner.bind('mousewheel', this.innerPaneMouseWheelListener);
  
        // show
        var initialDisplay = this.pane.options.initialDisplay;
  
        if (initialDisplay !== false) {
          this.show();
          if (this.pane.autoHide) {
              this.hiding = setTimeout($.proxy(this, 'hide'), parseInt(initialDisplay, 10) || 3000);
          }
        }
      }
docs: Scrollbar constructor.
  
  @param {Element|jQuery} element
  @api public