bug#8308: 23.3; Use utf-8 for writing abbrev file

[Leo]

On 2011-03-21 17:00 +0800, Eli Zaretskii wrote:
>> From: Leo <sdl.web@gmail.com>
>> Date: Mon, 21 Mar 2011 14:22:24 +0800
>> Cc: 
>> 
>> Is it OK to change the encoding for abbrev file to utf-8?
>
> What will that do to characters that are not unified into the range of
> valid Unicode code points?

That's a valid concern. But

,----
| M -- emacs-mule
| 
| Emacs 21 internal format used in buffer and string.
| Type: emacs-mule (Emacs 21 internal encoding)
| EOL type: Automatic selection from:
|       [emacs-mule-unix emacs-mule-dos emacs-mule-mac]
| This coding system can encode all emacs-mule charsets.
| 
| [back]
`----

,----[ (info "(elisp)Text Representations") ]
|    (1) This internal representation is based on one of the encodings
| defined by the Unicode Standard, called "UTF-8", for representing any
| Unicode codepoint, but Emacs extends UTF-8 to represent the additional
| codepoints it uses for raw 8-bit bytes and characters not unified with
| Unicode.
`----

Would you agree to use utf-8-emacs instead, which covers all characters.

>
> Can you tell what is the purpose of this change?

Make abbrev file editable to other editors.

Leo