* src/pgtkterm.c (pgtk_defined_color): support gtk special colors

* src/pgtkterm.c (pgtk_defined_color): support gtk special colors

Color functions take the frame

* src/gtkutil.c (xg_check_special_colors): pass frame as argument.
* src/pgtkfns.c (x_set_foreground_color, x_set_background_color,
x_set_cursor_color, pgtk_set_scroll_bar_foreground,
pgtk_set_scroll_bar_background, Fxw_color_defined_p,
Fxw_color_values): pass frame as argument.
* src/pgtkterm.c (pgtk_parse_color): take frame as argument.
(pgtk_lisp_to_color): take frame as argument, and pass it.

Remove pgtk_lisp_to_color

* src/pgtkfns.c (x_set_foreground_color, x_set_background_color,
x_set_cursor_color): use x_decode_color instead of pgtk_lisp_to_color.
(Fxw_color_defined_p, Fxw_color_values):
use pgtk_defined_color instead of pgtk_lisp_to_color.
* src/pgtkterm.c (pgtk_lisp_to_color): remove.

* src/gtkutil.c (xg_check_special_colors): change color format

* src/pgtkterm.h: remove pgtk_lisp_to_color declaration