* lisp/textmodes: Use lexical-binding

* lisp/textmodes: Use lexical-binding

* lisp/textmodes/enriched.el: Use lexical-binding.
(enriched-mode): Use `delete-dups` to avoid `add-to-list` on
a local variable.

* lisp/textmodes/makeinfo.el: Use lexical-binding.
(makeinfo-region): Remove unused var `filename-or-header`.

* lisp/textmodes/refbib.el: Use lexical-binding.
(r2b-put-field): Remove unused var `multi-line`.
(r2b-barf-output): Remove unused var `match`.

* lisp/textmodes/refer.el: Use lexical-binding.
(refer-find-entry-internal): Remove unused vars `old-buffer` and `found`.

* lisp/textmodes/reftex-auc.el: Use lexical-binding.
(LaTeX-add-bibitems): Declare function.
(reftex-plug-into-AUCTeX): Use `add-function` and `advice-add` so we
can properly unplug.

* lisp/textmodes/reftex-cite.el: Use lexical-binding.
(reftex-create-bibtex-file): Remove unused var `file`.
(reftex--found-list): Declare var.
(reftex-offer-bib-menu): Rename local var to `reftex--found-list`.

* lisp/textmodes/reftex-dcr.el: Use lexical-binding.
(reftex-use-itimer-in-xemacs): Delete XEmacs-only var.
(reftex-toggle-auto-view-crossref): Delete XEmacs-only code.
(reftex-start-itimer-once): Delete XEmacs-only function.

* lisp/textmodes/reftex-global.el: Use lexical-binding.
(reftex-isearch-push-state-function): Use a closure instead of `(lambda).

* lisp/textmodes/reftex-index.el: Use lexical-binding.
(mark-active, transient-mark-mode): Delete var declarations.
(reftex-index-mode-map): Remove XEmacs-only code.
Use `mapc` so we can use closures instead of hand-built lambdas.
(reftex-index-next, reftex-index-previous): Tweak interactive spec to
remove unused prefix arg and mark it as a motion command.
(reftex-index-phrases-font-lock-keywords)
(reftex-index-phrases-font-lock-keywords): Move initialization into
declaration.
(reftex-index-initialize-phrases-buffer, reftex-index-phrases-mode)
reftex-index-phrases-apply-to-region: Remove XEmacs-only code.
(TeX-master): Remove redundant declaration.
(reftex--chars-first): Rename dynvar from `chars-first`.  Adjust all uses.

* lisp/textmodes/reftex-parse.el: Use lexical-binding.

* lisp/textmodes/reftex-ref.el: Use lexical-binding.
(reftex-label): Remove always-nil var `text`.
(reftex-refstyle): Declare before first use.
(<toplevel>): Use closures rather than `eval` when building commands from
`reftex-ref-style-alist`.

* lisp/textmodes/reftex-sel.el: Use lexical-binding.
(reftex-select-label-mode-map, reftex-select-bib-mode-map):
Use `mapc` so we can use closures instead of hand-built lambdas.
(reftex-select-label-mode, reftex-select-bib-mode): Remove XEmacs-only code.
(reftex-select-data, reftex-select-prompt, reftex-refstyle):
Move declaration before first use.
(reftex--found-list, reftex--cb-flag, reftex--last-data)
(reftex--call-back, reftex--help-string): Move declaration before use,
and rename by adding `reftext--` prefix.  Adjust all uses in this file.
For `reftex--found-list` adjust corresponding uses in `reftex-cite.el`.
(reftex-select-item): Explicitly let-bind them.
Remove XEmacs-only code.

* lisp/textmodes/reftex-toc.el: Use lexical-binding.
(reftex-toc-mode-map, reftex-toc-mode, reftex-toc-restore-region)
(reftex-toc-next, reftex-toc-previous, reftex-toc-next-heading)
(reftex-toc-previous-heading, reftex-toggle-auto-toc-recenter
(reftex-make-separate-toc-frame): Remove XEmacs-only code.

* lisp/textmodes/reftex-vars.el: Use lexical-binding.

* lisp/textmodes/reftex.el: Use lexical-binding.
(reftex-mode-map, reftex-mode, reftex-fontify-select-label-buffer)
(reftex-verified-face): Remove XEmacs-only code.
(reftex-region-active-p, reftex-overlay-put, reftex-move-overlay)
(reftex-make-overlay, reftex-get-buffer-visiting, reftex-delete-overlay):
Redefine as obsolete aliases.  Replace all callers.
(current-message): Remove XEmacs-only definition.

* lisp/textmodes/remember.el: Use lexical-binding.

* lisp/textmodes/table.el (<toplevel>): Use closures rather than `(lambda)
to build commands.

* lisp/textmodes/texinfmt.el: Use lexical-binding.
(texinfo-example-start): Declare var.
(texinfo-format-region, texinfo-format-buffer-1): Remove unused var
`last-input-buffer`.
(texinfo-format-scan): Use `dlet` to bind `whitespace-silent`.
(texinfo-optional-braces-discard, texinfo-format-parse-line-args)
(texinfo-format-parse-args): Remove unused var `start`.
(texinfo-multitable-widths): Remove unused var `start-of-templates`.
(texinfo-multitable-item): Strength-reduce `eval` to `symbol-value`.
(texinfo-alias): Remove unused vars `start` and `args`.
(texinfo-defun-type symbol-property): Change the car to help the type
symbol rather than an expression returning it.
(texinfo-format-deffn): Remove corresponding `eval`.
(texinfo-clear): Remove unused var `value`.
(texinfo-format-ifeq): Remove unused var `end`.

* lisp/textmodes/texinfo.el: Use lexical-binding.
(tex-show-print-queue): Declare function.

* lisp/textmodes/texnfo-upd.el: Use lexical-binding.
(texinfo-start-menu-description): Remove unused var `end`.
(texinfo-insert-node-lines): Remove unused var `beginning-marker`.
(texinfo-multiple-files-update): Remove unused vars `next-node-name`
and `previous-node-name`.

* lisp/textmodes/two-column.el: Use lexical-binding.