(find-safe-coding-system): Moved to

(find-safe-coding-system): Moved to
mule-cmds.el.
(detect-coding-with-priority): New macro.
(detect-coding-with-language-environment): New function.

(string-to-sequence): Adjusted for the change of
multibyte-form handling (byte-base to char-base).
(store-substring): Likewise.
(truncate-string-to-width): Likewise.
(decompose-region): Likewise.
(decompose-string): Likewise.
(decompose-composite-char): Call string instead of concat-chars.