src/vs/editor/contrib/folding/hiddenRangeModel.ts/HiddenRangeModel/applyHiddenRanges
class HiddenRangeModel:	private applyHiddenRanges(newHiddenAreas: IRange[]) {
		this._hiddenRanges = newHiddenAreas;
		this._updateEventEmitter.fire(newHiddenAreas);
	}