Remove import

Author: sbuggay

front_end/panels/timeline/TimelineFlameChartDataProvider.ts

@@ -106,8 +106,6 @@ const i18nString = i18n.i18n.getLocalizedString.bind(undefined, str_);
 
 export class TimelineFlameChartDataProvider extends Common.ObjectWrapper.ObjectWrapper<EventTypes> implements
     PerfUI.FlameChart.FlameChartDataProvider {
-  private isReactNative = false;
-
   private droppedFramePatternCanvas: HTMLCanvasElement;
   private partialFramePatternCanvas: HTMLCanvasElement;
   private timelineDataInternal: PerfUI.FlameChart.FlameChartTimelineData|null = null;