src/vs/workbench/api/common/extHostNotebook.ts/ExtHostNotebookController/$provideNotebookCellStatusBarItems
class ExtHostNotebookController:	async $provideNotebookCellStatusBarItems(handle: number, uri: UriComponents, index: number, token: CancellationToken): Promise<INotebookCellStatusBarListDto | undefined> {
		const provider = this._notebookStatusBarItemProviders.get(handle);
		const revivedUri = URI.revive(uri);
		const document = this._documents.get(revivedUri);
		if (!document || !provider) {
			return;
		}

		const cell = document.getCellFromIndex(index);
		if (!cell) {
			return;
		}

		const result = await provider.provideCellStatusBarItems(cell.apiCell, token);
		if (!result) {
			return undefined;
		}

		const disposables = new DisposableStore();
		const cacheId = this._statusBarCache.add([disposables]);
		const resultArr = Array.isArray(result) ? result : [result];
		const items = resultArr.map(item => typeConverters.NotebookStatusBarItem.from(item, this._commandsConverter, disposables));
		return {
			cacheId,
			items
		};
	}