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Error thrown on _performLongPress while scrubbing in the chart

While scrubbing within the chart, a Null check operator used on a null value is thrown in _performLongPress. Taking a look at the code, it occurs when position is null. It looks like the linter caught the issue, but it was explicitly ignored using ignore: unnecessary_null_comparison. The null check on position occurs after it has been non-null asserted. If the null check is moved to the beginning of the if statement, the issue should be resolved. 

// ignore: unnecessary_null_comparison
if ((chart.trackballBehavior != null &&
        chart.trackballBehavior.enable == true &&
        _findSeries(position!) != null &&
        chart.trackballBehavior.activationMode ==
            ActivationMode.longPress) &&
    SeriesHelper.getSeriesRendererDetails(_findSeries(position)!).series
        is! ErrorBarSeries &&
    // ignore: unnecessary_null_comparison
    position != null &&
    zoomingBehaviorDetails.isPinching != true) {
  trackballRenderingDetails.isLongPressActivated = true;
  chart.trackballBehavior.builder != null
      ? trackballRenderingDetails.showTemplateTrackball(position)
      : _stateProperties.trackballBehaviorRenderer
          .onTouchDown(position.dx, position.dy);
}