* lisp/cus-edit.el (custom--initialize-widget-variables): New function.
(Custom-mode): Use it.
* lisp/cus-face.el (custom-theme-set-faces): Remove dead code. Obey
custom--inhibit-theme-enable.
* lisp/cus-theme.el (describe-theme, customize-themes)
(custom-theme-save): New commands.
(custom-new-theme-mode-map): Bind C-x C-s.
(custom-new-theme-mode): Use custom--initialize-widget-variables.
(customize-create-theme): New optional arg THEME.
(custom-theme-revert): Use it.
(custom-theme-visit-theme): Remove dead code.
(custom-theme-merge-theme): Use custom-available-themes.
(custom-theme-write): Make interactive.
(custom-theme-write): Use custom-theme-name-valid-p.
(describe-theme-1, custom-theme-choose-revert)
(custom-theme-checkbox-toggle, custom-theme-selections-toggle):
New funs.
(custom-theme-allow-multiple-selections): New option.
(custom-theme-choose-mode): New major mode.
* lisp/custom.el (custom-theme-set-variables): Remove dead code. Obey
custom--inhibit-theme-enable.
(custom--inhibit-theme-enable): New var.
(provide-theme): Obey it.
(load-theme): Replace load with manual read/eval, in order to
check for correctness. Use custom-theme-name-valid-p.
(custom-theme-name-valid-p): New function.
(custom-available-themes): Use it.
* lisp/help-mode.el (help-theme-def, help-theme-edit): New buttons.
* cus-edit.el (custom-face-widget-to-spec)
(custom-face-get-current-spec, custom-face-state): New functions.
(custom-face-set, custom-face-mark-to-save)
(custom-face-value-create, custom-face-state-set): Use them.
* cus-theme.el (custom-theme--listed-faces): New var.
(customize-create-theme): Use *Custom Theme* as the buffer name.
Set revert-buffer-function. Optional arg BUFFER. Insert all
faces listed in custom-theme--listed-faces.
(custom-theme-revert): New function.
(custom-theme-add-variable, custom-theme-add-face): Insert at the
bottom of the list.
(custom-theme-write): Prompt for theme name if empty.
(custom-theme-write-variables): Use dolist.
(custom-theme-write-faces): Handle hidden (collapsed) widgets.
(custom-theme-name, custom-theme-variables, custom-theme-faces)
(custom-theme-description): Add compiler defvars.
(customize-create-theme): Add doc to the "*New Custom Theme*"
buffer. Use `custom-new-theme-mode'.
(custom-theme-write): Put the created buffer in emacs-lisp-mode
and save it to the `custom-theme-directory'. Make this the
default directory of the buffer.
