GTK: Remove use of deprecated gtk_dialog_set_has_separator

chrome/browser/ui/gtk/about_chrome_dialog.cc

Index: chrome/browser/ui/gtk/about_chrome_dialog.cc
diff --git a/chrome/browser/ui/gtk/about_chrome_dialog.cc b/chrome/browser/ui/gtk/about_chrome_dialog.cc
index 04d182f5ac2f36e4368be82d4c53bc1ef955e4f5..9f2df3c900ebaa4755a64407f02649c52ce98174 100644
--- a/chrome/browser/ui/gtk/about_chrome_dialog.cc
+++ b/chrome/browser/ui/gtk/about_chrome_dialog.cc
@@ -115,7 +115,9 @@ void ShowAboutDialogForProfile(GtkWindow* parent, Profile* profile) {
   // The layout of this dialog is special because the logo should be flush
   // with the edges of the window.
   gtk_widget_set_name(dialog, "about-dialog");
+#if !GTK_CHECK_VERSION(2, 22, 0)
   gtk_dialog_set_has_separator(GTK_DIALOG(dialog), FALSE);
+#endif
 
   GtkWidget* close_button = gtk_dialog_add_button(GTK_DIALOG(dialog),
       GTK_STOCK_CLOSE, GTK_RESPONSE_CLOSE);