[gnome-system-monitor] Remove deprecated GTK+ symbol. Fixes bug 561963.

[Andre Klapper <aklapper src gnome org>]

commit c56e377efa9d7ffa77ea0f2f16bf0b316aaa379f
Author: Andre Klapper <a9016009 gmx de>
Date:   Fri May 28 21:14:17 2010 +0200

     Remove deprecated GTK+ symbol. Fixes bug 561963.

 src/gsm_color_button.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/src/gsm_color_button.c b/src/gsm_color_button.c
index e1634cc..f2379f4 100644
--- a/src/gsm_color_button.c
+++ b/src/gsm_color_button.c
@@ -714,7 +714,11 @@ gsm_color_button_clicked (GtkWidget * widget, GdkEventButton * event)
       color_dialog =
 	GTK_COLOR_SELECTION_DIALOG (color_button->priv->cs_dialog);
 
+#if GTK_CHECK_VERSION (2,18,0)
+      if (gtk_widget_is_toplevel (parent) && GTK_IS_WINDOW (parent))
+#else
       if (GTK_WIDGET_TOPLEVEL (parent) && GTK_IS_WINDOW (parent))
+#endif
 	{
 	  if (GTK_WINDOW (parent) !=
 	      gtk_window_get_transient_for (GTK_WINDOW (color_dialog)))