Freset: properly reset graphics objects (bug #35511) * graphics.in.h (base_graphics_object, graphics_object, root): add new method "get_factory_defaults_list" to retrieve factory defaults as property_list * graphics.in.h (base_graphics_object::reset_default_properties (void)): move definition to graphics.cc * graphics.cc (xreset_default_properties): new function to set a list of prop/val * graphics.cc (base_graphics_object::reset_default_properties): use xreset_default_properties, override with parents' defaults * graphics.cc (root_figure::reset_default_properties, figure::reset_default_properties, uitoolbar::reset_default_properties): same as above but first empty local defaults * graphics.cc (axes_figure::reset_default_properties): same as above but use "propeties.set_defaults" to reset properties to their factory value. * graphics.cc (axes_figure::properties::set_defaults): new "reset" mode, that does the same as "replace" but x/y/zlabels and title are reset instead of being deleting/recreating. * graphics.cc: add %!tests for Freset

#include <octave/oct.h>

DEFUN_DLD (globaldemo, args, , "Global Demo")
{
  octave_value retval;
  int nargin = args.length ();

  if (nargin != 1)
    print_usage ();
  else
    {
      std::string s = args(0).string_value ();
      if (! error_state)
        {
          octave_value tmp = get_global_value (s, true);
          if (tmp.is_defined ())
            retval = tmp;
          else
            retval = "Global variable not found";

          set_global_value ("a", 42.0);
        }
    }
  return retval;
}