xyTipsOn (xyTipsOn) {
        if (!arguments.length) {
            return this._xyTipsOn;
        }
        this._xyTipsOn = xyTipsOn;
        return this;
    }
Turn on/off the mouseover behavior of an individual data point which renders a circle and x/y axis
dashed lines back to each respective axis.  This is ignored if the chart
{@link CoordinateGridMixin#brushOn brush} is on
@param  {Boolean} [xyTipsOn=false]
@returns {Boolean|LineChart}