Description:
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The "node_get_cell_style" of the GtkCTree widget does not work, it just returns NULL. The same problem should apply to the GtkCList.

Reproduce code:
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<?php
dl( "php_gtk." . ( strstr( PHP_OS, "WIN") ? "dll" : "so"));
function delete_event() { return false; }
function destroy() { Gtk::main_quit(); }
$window = &new GtkWindow();
$window->set_default_size( 200, 200);
$window->connect('destroy', 'destroy');
$window->connect('delete-event', 'delete_event');
$tree	= &new GtkCTree( 1, 0, array( "Style"));
$window->add( $tree);
$window->show_all();

$node	= $tree->insert_node( null, null, array( "Text"), 5, null, null, null, null, false, false);
$nodestyle	= $tree->node_get_cell_style( $node, 0);
print_r( $nodestyle);//should be NOT null
$col1 = &new GdkColor(0, 56000, 0);
$nodestyle->base[GTK_STATE_NORMAL] = $col1;
$tree->node_set_cell_style( $node, 0, $nodestyle);
Gtk::main();
?>

Expected result:
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the cell style of the first tree cell should have a nice color