src/vs/platform/userData/common/fileUserDataProvider.ts/FileUserDataProvider/readFileStream
class FileUserDataProvider:	readFileStream(resource: URI, opts: IFileReadStreamOptions, token: CancellationToken): ReadableStreamEvents<Uint8Array> {
		const stream = newWriteableStream<Uint8Array>(data => VSBuffer.concat(data.map(data => VSBuffer.wrap(data))).buffer);
		(async () => {
			try {
				const contents = await this.readFile(resource);
				stream.end(contents);
			} catch (error) {
				stream.error(error);
				stream.end();
			}
		})();
		return stream;
	}