API: Remove setters and getters for default colormaps

This removes:
gtk_widget_set_default_colormap()
gtk_widget_get_default_colormap()
gtk_widget_get_default_visual()

Colormaps are gone, and the default visual is the system visual of the
default screen.

docs/reference/gtk/gtk3-sections.txt

@@ -4814,10 +4814,7 @@ gtk_widget_set_style
 gtk_widget_ensure_style
 gtk_widget_get_style
 gtk_widget_reset_rc_styles
-gtk_widget_set_default_colormap
 gtk_widget_get_default_style
-gtk_widget_get_default_colormap
-gtk_widget_get_default_visual
 gtk_widget_set_direction
 GtkTextDirection
 gtk_widget_get_direction

gtk/gtk.symbols

@@ -4214,10 +4214,8 @@ gtk_widget_get_child_requisition
 gtk_widget_get_child_visible
 gtk_widget_get_clipboard
 gtk_widget_get_composite_name
-gtk_widget_get_default_colormap
 gtk_widget_get_default_direction
 gtk_widget_get_default_style
-gtk_widget_get_default_visual
 gtk_widget_get_direction
 gtk_widget_get_display
 gtk_widget_get_double_buffered
@@ -4300,7 +4298,6 @@ gtk_widget_set_allocation
 gtk_widget_set_app_paintable
 gtk_widget_set_child_visible
 gtk_widget_set_composite_name
-gtk_widget_set_default_colormap
 gtk_widget_set_default_direction
 gtk_widget_set_direction
 gtk_widget_set_double_buffered

gtk/gtkwidget.c

@@ -8933,50 +8933,6 @@ gtk_widget_pop_composite_child (void)
     composite_child_stack--;
 }
 
-/**
- * gtk_widget_set_default_colormap:
- * @colormap: a #GdkColormap
- * 
- * Sets the default colormap to use when creating widgets.
- * gtk_widget_push_colormap() is a better function to use if
- * you only want to affect a few widgets, rather than all widgets.
- **/
-void
-gtk_widget_set_default_colormap (GdkColormap *colormap)
-{
-  g_return_if_fail (GDK_IS_COLORMAP (colormap));
-  
-  gdk_screen_set_default_colormap (gdk_colormap_get_screen (colormap),
-				   colormap);
-}
-
-/**
- * gtk_widget_get_default_colormap:
- * 
- * Obtains the default colormap used to create widgets.
- *
- * Return value: (transfer none): default widget colormap
- **/
-GdkColormap*
-gtk_widget_get_default_colormap (void)
-{
-  return gdk_screen_get_default_colormap (gdk_screen_get_default ());
-}
-
-/**
- * gtk_widget_get_default_visual:
- * 
- * Obtains the visual of the default colormap. Not really useful;
- * used to be useful before gdk_colormap_get_visual() existed.
- *
- * Return value: (transfer none): visual of the default colormap
- **/
-GdkVisual*
-gtk_widget_get_default_visual (void)
-{
-  return gdk_colormap_get_visual (gtk_widget_get_default_colormap ());
-}
-
 static void
 gtk_widget_emit_direction_changed (GtkWidget        *widget,
 				   GtkTextDirection  old_dir)

gtk/gtkwidget.h

@@ -877,12 +877,7 @@ void gtk_widget_style_get          (GtkWidget	     *widget,
 
 /* Set certain default values to be used at widget creation time.
  */
-void	     gtk_widget_set_default_colormap (GdkColormap *colormap);
 GtkStyle*    gtk_widget_get_default_style    (void);
-#ifndef GDK_MULTIHEAD_SAFE
-GdkColormap* gtk_widget_get_default_colormap (void);
-GdkVisual*   gtk_widget_get_default_visual   (void);
-#endif
 
 /* Functions for setting directionality for widgets
  */