bug#51167: 29.0.50; org-indent-line broken

bug#51167: 29.0.50; org-indent-line broken

[Andreas Röhler]

With following stuff in org-mode buffer:

* bla
asd

M-x org-indent-line RET on second line has no effect.

In GNU Emacs 29.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 
3.24.25, cairo version 1.16.0)
  of 2021-10-12
Repository revision: 7e185bc9bae85ac3b50f9b7bd4b3c33bb8a016a8
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12101001
System Description: Ubuntu 21.04

Configured using:
  'configure --with-json -with-modules --with-mailutils'

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON
LIBOTF LIBSELINUX LIBXML2 MODULES NOTIFY INOTIFY PDUMPER PNG RSVG
SECCOMP SOUND THREADS TIFF TOOLKIT_SCROLL_BARS X11 XDBE XIM XPM GTK3
ZLIB

Important settings:
   value of $LC_MONETARY: de_DE.UTF-8
   value of $LC_NUMERIC: de_DE.UTF-8
   value of $LC_TIME: de_DE.UTF-8
   value of $LANG: en_US.UTF-8
   value of $XMODIFIERS: @im=ibus
   locale-coding-system: utf-8-unix

Major mode: Org

Minor modes in effect:
   tooltip-mode: t
   global-eldoc-mode: t
   show-paren-mode: t
   electric-indent-mode: t
   mouse-wheel-mode: t
   tool-bar-mode: t
   menu-bar-mode: t
   file-name-shadow-mode: t
   global-font-lock-mode: t
   font-lock-mode: t
   blink-cursor-mode: t
   auto-composition-mode: t
   auto-encryption-mode: t
   auto-compression-mode: t
   line-number-mode: t
   indent-tabs-mode: t
   transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug sendmail shortdoc help-fns radix-tree
org-element avl-tree generator ol-eww eww xdg url-queue thingatpt mm-url
ol-rmail ol-mhe ol-irc ol-info ol-gnus nnselect gnus-search eieio-opt
cl-extra help-mode speedbar ezimage dframe gnus-art mm-uu mml2015
mm-view mml-smime smime dig gnus-sum shr kinsoku svg dom browse-url url
url-proxy url-privacy url-expand url-methods url-history url-cookie
url-domsuf url-util url-parse url-vars mailcap gnus-group gnus-undo
gnus-start gnus-dbus dbus xml gnus-cloud nnimap nnmail mail-source utf7
netrc nnoo parse-time gnus-spec gnus-int gnus-range message rmc puny
rfc822 mml mml-sec epa derived epg rfc6068 epg-config mm-decode
mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
gnus-win gnus nnheader gnus-util rmail rmail-loaddefs auth-source cl-seq
eieio eieio-core cl-macs eieio-loaddefs password-cache json map rfc2047
rfc2045 ietf-drums text-property-search mail-utils mm-util mail-prsvr
wid-edit ol-docview doc-view jka-compr image-mode exif dired
dired-loaddefs ol-bibtex bibtex iso8601 ol-bbdb ol-w3m ol-doi
org-link-doi org ob ob-tangle ob-ref ob-lob ob-table ob-exp org-macro
org-footnote org-src ob-comint org-pcomplete pcomplete comint ansi-color
ring org-list org-faces org-entities time-date noutline outline
easy-mmode org-version ob-emacs-lisp ob-core ob-eval org-table ol rx
org-keys oc seq gv subr-x byte-opt bytecomp byte-compile cconv
org-compat advice org-macs org-loaddefs format-spec find-func cal-menu
calendar cal-loaddefs cl-loaddefs cl-lib iso-transl tooltip eldoc paren
electric uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel
term/x-win x-win term/common-win x-dnd tool-bar dnd fontset image
regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode
prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu
timer select scroll-bar mouse jit-lock font-lock syntax font-core
term/tty-colors frame minibuffer cl-generic cham georgian utf-8-lang
misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms
cp51932 hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese composite emoji-zwj charscript charprop case-table
epa-hook jka-cmpr-hook help simple abbrev obarray cl-preloaded nadvice
button loaddefs faces cus-face macroexp files window text-properties
overlay sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote threads dbusbind inotify
dynamic-setting system-font-setting font-render-setting cairo
move-toolbar gtk x-toolkit x multi-tty make-network-process emacs)

Memory information:
((conses 16 275083 20007)
  (symbols 48 43076 1)
  (strings 32 115362 3554)
  (string-bytes 1 2702402)
  (vectors 16 37614)
  (vector-slots 8 413285 24472)
  (floats 8 294 121)
  (intervals 56 377 0)
  (buffers 992 13))