* src/haikufns.c (haiku_change_tab_bar_height):
* src/nsfns.m (ns_change_tab_bar_height):
* src/pgtkfns.c (pgtk_change_tab_bar_height):
* src/w32fns.c (w32_change_tab_bar_height):
* src/xfns.c (x_change_tab_bar_height): Do not round tab bar
height up.  (bug#59285, bug#59271)

* lisp/frame.el (window-system-version): Delete variable.
* src/dispnew.c (syms_of_display) <Vwindow_system_version>:
Delete DEFVAR, obsolete since 24.3.
(init_display_interactive, syms_of_display_for_pdumper):
* src/msdos.c (internal_terminal_init):
* src/nsterm.m (ns_term_init):
* src/pgtkfns.c (pgtk_display_info_for_name):
* src/w32fns.c (w32_display_info_for_name, Fx_open_connection):
* src/xfns.c (x_display_info_for_name, Fx_open_connection): Don't
set above deleted variable.
* admin/admin.el (set-version): Don't update above deleted
variable in msdos.c.
* lisp/textmodes/artist.el (artist-submit-bug-report): Don't use
above deleted variable.

* doc/lispref/frames.texi (Management Parameters): Document
`use-frame-synchronization'.
* etc/NEWS: Update entry.

* src/frame.c (frame_parms): New frame parameter
`use-frame-synchronization'.
(syms_of_frame): New defsym.
* src/haikufns.c (haiku_frame_parm_handlers):
* src/nsfns.m (ns_frame_parm_handlers):
* src/pgtkfns.c (pgtk_frame_parm_handlers):
* src/w32fns.c (w32_frame_parm_handlers): Update frame param
handlers correctly.
* src/xfns.c (x_set_use_frame_synchronization): New function.
(Fx_create_frame): Set default value of said parameter.
(x_frame_parm_handlers): Add handler.

* src/xterm.c (x_sync_wait_for_frame_drawn_event): Clear
parameter if sync fails.

* src/haikufns.c (Fx_show_tip):
(syms_of_haikufns):
* src/nsfns.m (Fx_show_tip):
(syms_of_nsfns):
* src/pgtkfns.c (Fx_show_tip):
(syms_of_pgtkfns):
* src/xfns.c (Fx_show_tip):
(syms_of_xfns): Add assertion and adjust default values.

* configure.ac (EMACS_CONFIG_FEATURES):
* etc/NEWS:
* lisp/dnd.el (dnd-begin-text-drag):
* src/pgtkfns.c (Fx_display_mm_height, Fx_display_mm_width):
(Fx_display_backing_store, Fx_display_visual_class):
* src/xterm.c: Fix repeated "the".  (Bug#56341)

Copyright-paperwork-exempt: yes

* src/alloc.c (deadp):
* src/buffer.c (reset_buffer_local_variables, candidate_buffer)
(Fkill_buffer, Fbuffer_swap_text, Fmake_overlay, Fmove_overlay):
* src/callint.c (Fcall_interactively):
* src/coding.c (decode_coding_object, encode_coding_object)
(code_convert_region, Ffind_operation_coding_system):
* src/comp.c (Fcomp_el_to_eln_rel_filename):
* src/conf_post.h (RE_TRANSLATE_P):
* src/data.c (Fkill_local_variable, Fash, expt_integer):
* src/dired.c (file_name_completion):
* src/dispnew.c (set_window_cursor_after_update, update_frame_1)
(Fframe_or_buffer_changed_p):
* src/doc.c (Fdocumentation, Fdocumentation_property)
(default_to_grave_quoting_style):
* src/editfns.c (Fconstrain_to_field, save_excursion_save)
(save_excursion_restore, Fngettext):
* src/eval.c (Fautoload, un_autoload, specbind):
* src/fileio.c (Fmake_temp_file_internal):
* src/fns.c (string_char_to_byte, string_byte_to_char)
(Fnthcdr, Fnreverse):
* src/indent.c (vmotion):
* src/inotify.c (add_watch):
* src/keyboard.c (command_loop_1, read_char)
(read_char_minibuf_menu_prompt):
* src/lread.c (oblookup):
* src/macfont.m (macfont_descriptor_entity, macfont_open):
* src/minibuf.c (Finnermost_minibuffer_p, Ftry_completion)
(Ftest_completion):
* src/nsfns.m (ns_set_icon_name):
* src/pdumper.c (dump_queue_dequeue):
* src/pgtkfns.c (pgtk_set_icon_type, pgtk_set_icon_name):
* src/process.c (Faccept_process_output):
* src/textprop.c (set_text_properties):
* src/w32fns.c (w32_set_icon_type, w32_set_icon_name):
* src/w32select.c (validate_coding_system):
* src/window.c (decode_next_window_args, window_loop)
(save_window_save):
* src/xdisp.c (wset_redisplay):
* src/xfaces.c (Fx_family_fonts, resolve_face_name)
(gui_supports_face_attributes_p):
* src/xfns.c (x_set_icon_type, x_set_icon_name):
* src/xselect.c (clean_local_selection_data):
Use BASE_EQ instead of EQ where it is obvious that neither argument
can be a symbol with properties or at least one argument is a
non-symbol.

Qunbound is uninterned and can therefore never be EQ to any symbol
with position.

* src/buffer.c (Fbuffer_local_value, buffer_lisp_local_variables)
(buffer_local_variables_1):
* src/bytecode.c (exec_byte_code):
* src/comp.c (compile_function, Fcomp__compile_ctxt_to_file):
* src/composite.c (composition_gstring_cache_clear_font):
* src/data.c (Fboundp, Fsymbol_value, set_internal)
(Fdefault_boundp, Fdefault_value, Fmake_variable_buffer_local):
* src/emacs-module.c (module_global_reference_p):
* src/eval.c (Fdefault_toplevel_value, defvar)
(run_hook_with_args):
* src/fns.c (hash_put, Fmaphash):
* src/font.c (font_put_extra):
* src/frame.c (gui_set_frame_parameters)
(gui_frame_get_and_record_arg, gui_default_parameter)
(gui_figure_window_size):
* src/haikufns.c (get_geometry_from_preferences)
(haiku_create_frame, haiku_create_tip_frame):
* src/haikuterm.c (haiku_draw_text_decoration)
(haiku_default_font_parameter):
* src/json.c (lisp_to_json_nonscalar_1):
* src/keymap.c (access_keymap_1, access_keymap, current_minor_maps):
* src/lread.c (readevalloop, define_symbol):
* src/minibuf.c (read_minibuf, Ftry_completion):
(Fall_completions, Ftest_completion):
* src/pgtkfns.c (pgtk_default_font_parameter, Fx_create_frame)
(x_create_tip_frame):
* src/pgtkselect.c (Fpgtk_own_selection_internal):
* src/print.c (print):
* src/profiler.c (evict_lower_half, record_backtrace):
* src/terminal.c (create_terminal):
* src/textprop.c (set_properties):
* src/w32fns.c (my_create_window, w32_icon)
(w32_default_font_parameter, Fx_create_frame)
(w32_create_tip_frame):
* src/w32term.c (w32_draw_glyph_string):
* src/xdisp.c (handle_single_display_spec)
(cursor_row_fully_visible_p, calc_pixel_width_or_height):
* src/xfns.c (x_default_scroll_bar_color_parameter, x_icon_verify)
(x_icon, x_default_font_parameter, Fx_create_frame)
(x_create_tip_frame):
* src/xselect.c (x_handle_selection_request):
* src/xterm.c (x_draw_glyph_string, x_term_init):
Use BASE_EQ instead of EQ when comparing with Qunbound.

* src/pgtkfns.c (Fx_create_frame): Make default
`child-frame-border-width' nil.  (bug#55588)

* src/gtkutil.c (xg_check_special_colors): Handle child frames
correctly.
* src/pgtkfns.c (pgtk_set_child_frame_border_width): Synchronize
code from X.  (bug#55588)
* src/pgtkmenu.c (pgtk_menu_show, pgtk_dialog_show): Allow in
child frames.  There are no problems here.
* src/pgtkterm.c (pgtk_mouse_position): Clean up coding style.