GTK: Create the start of a compatibility header wrapping deprecated methods.

ui/base/gtk/gtk_windowing.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/base/gtk/gtk_windowing.h"
 
 #include <gdk/gdkx.h>
 
 #include "base/logging.h"
+#include "ui/base/gtk/gtk_compat.h"
 #include "ui/base/x/x11_util.h"
 
 namespace ui {
 
 void StackPopupWindow(GtkWidget* popup, GtkWidget* toplevel) {
-  DCHECK(GTK_IS_WINDOW(popup) && GTK_WIDGET_TOPLEVEL(popup) &&
-         GTK_WIDGET_REALIZED(popup));
-  DCHECK(GTK_IS_WINDOW(toplevel) && GTK_WIDGET_TOPLEVEL(toplevel) &&
-         GTK_WIDGET_REALIZED(toplevel));
+  DCHECK(GTK_IS_WINDOW(popup) && gtk_widget_is_toplevel(popup) &&
+         gtk_widget_get_realized(popup));
+  DCHECK(GTK_IS_WINDOW(toplevel) && gtk_widget_is_toplevel(toplevel) &&
+         gtk_widget_get_realized(toplevel));
 
   // Stack the |popup| window directly above the |toplevel| window.
   // The popup window is a direct child of the root window, so we need to
   // find a similar ancestor for the toplevel window (which might have been
   // reparented by a window manager).  We grab the server while we're doing
   // this -- otherwise, we'll get an error if the window manager reparents the
   // toplevel window right after we call GetHighestAncestorWindow().
   gdk_x11_display_grab(gtk_widget_get_display(toplevel));
   XID toplevel_window_base = ui::GetHighestAncestorWindow(
       ui::GetX11WindowFromGtkWidget(toplevel),
       ui::GetX11RootWindow());
   if (toplevel_window_base) {
     XID window_xid = ui::GetX11WindowFromGtkWidget(popup);
     XID window_parent = ui::GetParentWindow(window_xid);
     if (window_parent == ui::GetX11RootWindow()) {
       ui::RestackWindow(window_xid, toplevel_window_base, true);
     } else {
       // The window manager shouldn't reparent override-redirect windows.
       DLOG(ERROR) << "override-redirect window " << window_xid
                   << "'s parent is " << window_parent
                   << ", rather than root window "
                   << ui::GetX11RootWindow();
     }
   }
   gdk_x11_display_ungrab(gtk_widget_get_display(toplevel));
 }
 
 }  // namespace ui