code: function (v) {
              this._scrollDistance = Math.max(0, Math.min(this._getMaxScrollDistance(), v));
              // Mark that the scroll distance has changed so that after the view is checked, the CSS
              // transformation can move the header.
              this._scrollDistanceChanged = true;
              this._checkScrollingControls();
          }
docs: Sets the distance in pixels that the tab header should be transformed in the X-axis.
  @param {?} v
  @return {?}