isActiveSeries = function isActiveSeries(seriesIndex) {
          return w.globals.collapsedSeriesIndices.indexOf(seriesIndex) === -1 && w.globals.ancillaryCollapsedSeriesIndices.indexOf(seriesIndex) === -1;
        }
* When hovering over series, you need to capture which series is being hovered on.
* This function will return both capturedseries index as well as inner index of that series
@memberof Utils
@param {object}
- hoverArea = the rect on which user hovers
- elGrid = dimensions of the hover rect (it can be different than hoverarea)