* src/gtkutil.h: Declare 'xg_set_gtk_theme_dark_mode',
'xg_update_dark_mode_for_all_displays',
'xg_set_initial_dark_mode'.
* src/gtkutil.c (xg_set_gtk_theme_dark_mode): Toggle PGTK dark mode.
(xg_update_dark_mode_for_all_displays): Toggle PGTK dark mode for all
displays.
(xg_set_initial_dark_mode): Determine PGTK dark mode preference and set.
(xg_create_frame_widgets): Set PGTK dark mode preference for widgets.
(xg_create_frame_outer_widgets): Set PGTK dark mode preference for outer
widgets.
* src/xsettings.h: Declare 'xg_get_system_dark_mode'.
* src/xsettings.c (something_changed_gsettingsCB): Update PGTK dark mode
setting.
(xg_get_system_dark_mode): Determine PGTK dark mode preference.
GSETTINGS_COLOR_SCHEME: Defined and set to "color-scheme".
* etc/NEWS: Document automatic dark mode toggling.
(Bug#79689)

Run "TZ=UTC0 admin/update-copyright".

* src/xsettings.c (xft_settings_event):
* src/xsettings.h: Return if the event was handled.
* src/xterm.c (handle_one_xevent): If it was, don't handle the
event any further.

If present, apply the gsettings font hinting and antialiasing
entries when creating a font in cairo.  Do this at
initialization and when the entries change, re-rendering the
frames.

* src/ftcrfont.c (ftcrfont_open): Use the font_options derived
from gsettings when opening a font.
(ftcrfont_cached_font_ok): Report a cached font as invalid if
its font options differ from the current options inside
gsettings.
* src/xsettings.c (apply_gsettings_font_hinting)
(apply_gsettings_font_alias, apply_gsettings_font_rgba_order):
Convert the settings from GSettings to the cairo_font_options_t
object.
(init_gsettings, something_changed_gsettingsCB): Invoke the
apply functions if the relevant settings changed.
(store_font_options_changed): Store an event to re-render the
fonts.
(xsetting_get_font_options)
* src/xsettings.h (xsettings_get_font_options): New function.

* src/xsettings.h [!HAVE_PGTK]: Include dispextern.h and remove
duplicate definition of Display_Info.

836be7a112 ; * etc/refcards/ru-refcard.tex: Update Copyright year.
86cbc6ee4a * lisp/net/tramp-sh.el: Adapt copyright year
ebe8772f65 ; Minor fixes related to copyright years
23c1ee6989 ; * test/manual/etags/ETAGS.good_N: Adjust to copyright ye...
8d3fc7ec89 * src/xfaces.c (face_for_font): Make 'hash' be uintptr_t.
19dcb237b5 ; Add 2022 to copyright years.

# Conflicts:
#	etc/NEWS
#	etc/refcards/ru-refcard.tex
#	lib/cdefs.h
#	lisp/erc/erc-dcc.el
#	lisp/erc/erc-imenu.el
#	lisp/erc/erc-replace.el
#	lisp/image-dired.el
#	lisp/progmodes/xref.el
#	m4/alloca.m4
#	m4/byteswap.m4
#	m4/errno_h.m4
#	m4/getopt.m4
#	m4/gnulib-common.m4
#	m4/inttypes.m4
#	m4/stddef_h.m4
#	m4/stdint.m4
#	m4/sys_socket_h.m4