Fixes #358.
R=rsc
CC=r
https://golang.org/cl/164043
// ToUpper returns a copy of the string s with all Unicode letters mapped to their upper case.
func ToUpper(s string) string { return Map(unicode.ToUpper, s) }
-// ToUpper returns a copy of the string s with all Unicode letters mapped to their lower case.
+// ToLower returns a copy of the string s with all Unicode letters mapped to their lower case.
func ToLower(s string) string { return Map(unicode.ToLower, s) }
// ToTitle returns a copy of the string s with all Unicode letters mapped to their title case.