Include limits.h and errno.h.

Include limits.h and errno.h.
Declare externs from other files.
(w32_in_use): New variable.
(check_w32, have_menus_p, x_set_title, w32_msg_worker,
find_deferred_msg, send_deferred_msg, complete_deferred_msg,
Fw32_focus_frame, W32-send-sys-command): New functions.
(last_mouse_movement_time): Delete variable.

(x_frame_parms): Alphabetize.  Add title parm.
(x_set_icon_name): Use title if set.
(x_set_menu_bar_lines): Ensure client area remains the same.
(x_set_name): Don't update if the name is the same.
Use title for name if available.
(x_icon): Initial support for creating window iconified.
(x_display_info_for_name): Set w32_in_use.
(Fx_open_connection): Validate Vwindow_system.  Set w32_in_use.

(w32_create_window): Set window size to frame dimensions.
Set font width, line height, border, scrollbar indexes.
Don't set X and Y units indexes.
(w32_msg_pump): Renamed from windows_msg_worker.
Make static.  Don't post done message. No longer handle
create scrollbar message.  Don't abort on anomalous messages.
Return when completion detected.
(w32_wnd_proc): Keep track of button state.
For WINDOWPOSCHANGING, force window dimensions to be multiples
of character dimensions.
Handle CREATESCROLLBAR.
Use correct arguments for SHOWWINDOW.
For SETWINDOWPOS, use WINDOWPOS structure.

(my_create_window): Abort if message post fails.
(Fx_create_frame): Use title instead of name.
GC protect frame before make_frame_without_minibuffer.
Set icon name.
Use courier new as default font (has bold and italic).
Set BufferPredicate and Title default parameters.

(x_to_w32_weight): Support semibold weight.
(x_to_w32_charset): Map # to numeric charset identifier.
(w32_to_x_charset): Encode unknown charsets as a number.
(enum_font_cb2): Don't restrict to ANSI and OEM charsets.

(Fx_color_values): Set high and low words of color values.

(syms_of_w32fns): Zero w32_in_use.  defsubr new functions.

(w32_wnd_proc): Pass on WM_DISPLAYCHANGE messages.

(win32_wnd_proc): Capture and handle WM_MOUSEWHEEL events.
Capture and handle WM_EMACS_TRACKPOPUPMENU events.
Allow a dragged selection from a popup menu started up
by a mouse down event.
(x_to_win32_color): Support for X Windows RGB string specifications.