src/vs/workbench/contrib/comments/browser/commentThreadRangeDecorator.ts/CommentThreadRangeDecorator/constructor
class CommentThreadRangeDecorator:	constructor(commentService: ICommentService) {
		super();
		const decorationOptions: IModelDecorationOptions = {
			description: CommentThreadRangeDecorator.description,
			isWholeLine: false,
			zIndex: 20,
			className: 'comment-thread-range'
		};

		this.decorationOptions = ModelDecorationOptions.createDynamic(decorationOptions);

		const activeDecorationOptions: IModelDecorationOptions = {
			description: CommentThreadRangeDecorator.description,
			isWholeLine: false,
			zIndex: 20,
			className: 'comment-thread-range-current'
		};

		this.activeDecorationOptions = ModelDecorationOptions.createDynamic(activeDecorationOptions);
		this._register(commentService.onDidChangeCurrentCommentThread(thread => {
			this.updateCurrent(thread);
		}));
		this._register(commentService.onDidUpdateCommentThreads(() => {
			this.updateCurrent(undefined);
		}));
	}