extensions/typescript-language-features/web/webServer.ts/hrtime
function hrtime(previous?: number[]) {
	const now = self.performance.now() * 1e-3;
	let seconds = Math.floor(now);
	let nanoseconds = Math.floor((now % 1) * 1e9);
	// NOTE: This check is added probably because it's missed without strictFunctionTypes on
	if (previous?.[0] !== undefined && previous?.[1] !== undefined) {
		seconds = seconds - previous[0];
		nanoseconds = nanoseconds - previous[1];
		if (nanoseconds < 0) {
			seconds--;
			nanoseconds += 1e9;
		}
	}
	return [seconds, nanoseconds];
}