Merge 2022-07 LWG Motion 23

P2419R2 Clarify handling of encodings in localized formatting of chrono types

Author: tkoeppe

source/time.tex

@@ -10509,6 +10509,11 @@
 the formats specified in ISO 8601:2004 shall be used where so described.
 Some of the conversion specifiers
 depend on the formatting locale.
+If the string literal encoding is a Unicode encoding form and
+the locale is among
+an \impldef{locales with Unicode support for chrono types} set of locales,
+each replacement that depends on the locale is performed as if
+the replacement character sequence is converted to the string literal encoding.
 If the formatted object does not contain the information
 the conversion specifier refers to,
 an exception of type \tcode{format_error} is thrown.