* wl.el (wl-init): Set `elmo-get-folder-function' as

* wl.el (wl-init): Set `elmo-get-folder-function' as
`wl-folder-make-elmo-folder'.

* wl-spam.el (wl-summary-exec-action-spam): Use
`wl-folder-make-elmo-folder' instead of `elmo-make-folder'.

* wl-folder.el (wl-folder-make-elmo-folder): New function.
(wl-draft-get-folder): Use `wl-folder-make-elmo-folder' instead of
`elmo-make-folder'.
(wl-folder-get-elmo-folder): Ditto.
(wl-folder-create-subr): Simplify.

* elmo.el (elmo-get-folder-function): New variable.
(elmo-get-folder): New function.
(elmo-folder-rename): Call `elmo-make-folder' with specified
mime-charset.

* elmo-split.el (elmo-split): Use `elmo-get-folder' instead of
`elmo-make-folder'.
(elmo-split-subr): Ditto.

* elmo-multi.el (elmo-folder-initialize): Ditto.

* elmo-internal.el (elmo-folder-list-subfolders): Ditto.

* elmo-flag.el (elmo-flag-folder-delete-message): Ditto.
(elmo-flag-get-folder): Ditto.

* elmo-filter.el (elmo-folder-initialize): Ditto.

* elmo-access.el (elmo-folder-initialize): Ditto.
(elmo-access-folder-update-children): Ditto.

* elmo-dop.el (elmo-dop-queue-flush): Ditto.
(elmo-dop-queue-flush): Ditto.
(elmo-folder-append-buffer-dop-delayed): Ditto.
(elmo-dop-spool-folder): Call `elmo-make-folder' with specified
mime-charset.

* elmo-pipe.el (elmo-folder-initialize): Use `elmo-get-folder'
instead of `elmo-make-folder'.
(elmo-folder-rename): Ditto.  Use `elmo-folder-rename' to
destination folder instead of send `elmo-folder-rename-internal'.

* elmo-shimbun.el (elmo-folder-list-subfolders): Use `shimbun'
slot of subfolder instead of create it.