Merge from origin/emacs-26

Merge from origin/emacs-26

0589de5 (origin/emacs-26) Fix markup of fake keys in the ELisp manual
82d4b98 Avoid errors in Auto Revert mode
a3b1935 Mention empty strings in file name expansion, emacs lisp refe...
a38da0d cc-mode.texi: Work around makeinfo alignment bug.  Fix proble...
464ee80 Warn against recursive invocations of 'buffer-list-update-hoo...
60b5c10 Provide more details in doc-string of 'delete-windows-on' (Bu...
f0be0f1 Improve documentation of 'delete-windows-on'
f1bddc7 * lisp/frame.el (make-frame-command): Doc fix.  (Bug#34715)
2848623 Avoid undefined behavior in gdb-mi.el
dbf1837 * lisp/window.el (fit-frame-to-buffer): Make doc-string more ...
099ef44 Minor spelling and grammar fixes (bug#34756)
52fd400 Minor improvement of documentation of '(when CONDITION . SPEC)'
f872b65 Improve documentation of 'auto-coding-functions'
04cad5e Fix visiting XML files with non-Unix EOL format
a89fabe Update example major mode code in Elisp manual

# Conflicts:
#	lisp/autorevert.el
#	lisp/window.el