GTK: More raw struct access removal, this time focusing on GtkDialog.

chrome/browser/ui/gtk/task_manager_gtk.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 "chrome/browser/ui/gtk/task_manager_gtk.h"
 
 #include <gdk/gdkkeysyms.h>
 
 #include <algorithm>
 #include <set>
@@ skipping 481 matching lines @@
   gtk_dialog_set_response_sensitive(GTK_DIALOG(dialog_),
                                     kTaskManagerResponseKill, FALSE);
 
   GtkWidget* link = gtk_chrome_link_button_new(
       l10n_util::GetStringUTF8(IDS_TASK_MANAGER_ABOUT_MEMORY_LINK).c_str());
   gtk_dialog_add_action_widget(GTK_DIALOG(dialog_), link,
                                kTaskManagerAboutMemoryLink);
 
   // Setting the link widget to secondary positions the button on the left side
   // of the action area (vice versa for RTL layout).
-  gtk_button_box_set_child_secondary(
-      GTK_BUTTON_BOX(GTK_DIALOG(dialog_)->action_area), link, TRUE);
+  GtkWidget* action_area = gtk_dialog_get_action_area(GTK_DIALOG(dialog_));
+  gtk_button_box_set_child_secondary(GTK_BUTTON_BOX(action_area), link, TRUE);
 
   ConnectAccelerators();
 
-  gtk_box_set_spacing(GTK_BOX(GTK_DIALOG(dialog_)->vbox),
-                      ui::kContentAreaSpacing);
+  GtkWidget* content_area = gtk_dialog_get_content_area(GTK_DIALOG(dialog_));
+  gtk_box_set_spacing(GTK_BOX(content_area), ui::kContentAreaSpacing);
 
   destroy_handler_id_ = g_signal_connect(dialog_, "destroy",
                                          G_CALLBACK(OnDestroyThunk), this);
   g_signal_connect(dialog_, "response", G_CALLBACK(OnResponseThunk), this);
   // GTK does menu on mouse-up while views does menu on mouse-down,
   // so connect to different handlers.
 #if defined(TOOLKIT_VIEWS)
   g_signal_connect(dialog_, "button-release-event",
                    G_CALLBACK(OnButtonEventThunk), this);
 #else
@@ skipping 518 matching lines @@
                                           guint keyval,
                                           GdkModifierType modifier) {
   if (keyval == GDK_w && modifier == GDK_CONTROL_MASK) {
     // The GTK_RESPONSE_DELETE_EVENT response must be sent before the widget
     // is destroyed.  The deleted object will receive gtk signals otherwise.
     gtk_dialog_response(GTK_DIALOG(dialog_), GTK_RESPONSE_DELETE_EVENT);
   }
 
   return TRUE;
 }