src/vs/editor/contrib/folding/hiddenRangeModel.ts/HiddenRangeModel/dispose
class HiddenRangeModel:	public dispose() {
		if (this.hiddenRanges.length > 0) {
			this._hiddenRanges = [];
			this._updateEventEmitter.fire(this._hiddenRanges);
		}
		if (this._foldingModelListener) {
			this._foldingModelListener.dispose();
			this._foldingModelListener = null;
		}
	}