// using WTF-8 instead of UTF-8 encoding.
func UTF16ToString(s []uint16) string {
	maxLen := 0
	for i, v := range s {
		if v == 0 {
			s = s[0:i]
			break
		}
		switch {
		case v <= rune1Max:
			maxLen += 1
		case v <= rune2Max:
			maxLen += 2
		default:
			// r is a non-surrogate that decodes to 3 bytes,
			// or is an unpaired surrogate (also 3 bytes in WTF-8),
			// or is one half of a valid surrogate pair.