* wl-summary.el (wl-summary-set-message-modified):

* wl-summary.el (wl-summary-set-message-modified):
Call wl-summary-set-mark-modified.
(wl-summary-delete-messages-on-buffer): Call
wl-folder-set-folder-updated instead of wl-folder-update-unread.
(wl-summary-sync-update): Call elmo-folder-length instead of
elmo-folder-messages.
(wl-summary-insert-headers): Don't call
elmo-folder-list-message-entities.

* elmo.el (elmo-folder-list-message-entities): Define as inline function.
(elmo-folder-messages): Abolish.

* elmo-multi.el (elmo-folder-check): Call elmo-folder-check for each folder.
(elmo-folder-synchronize): Define.
(elmo-message-entity): Define.