gtk: Use gtk_dialog_get_content_area() throughout.

chrome/browser/ui/gtk/first_run_dialog.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/first_run_dialog.h"
 
 #include <string>
 #include <vector>
 
 #include "base/i18n/rtl.h"
@@ skipping 250 matching lines @@
   gtk_util::AddButtonToDialog(dialog_,
       l10n_util::GetStringUTF8(IDS_FIRSTRUN_DLG_OK).c_str(),
       GTK_STOCK_APPLY, GTK_RESPONSE_ACCEPT);
   gtk_window_set_deletable(GTK_WINDOW(dialog_), FALSE);
 
   gtk_window_set_resizable(GTK_WINDOW(dialog_), FALSE);
 
   g_signal_connect(dialog_, "delete-event",
                    G_CALLBACK(gtk_widget_hide_on_delete), NULL);
 
-  GtkWidget* content_area = GTK_DIALOG(dialog_)->vbox;
+  GtkWidget* content_area = gtk_dialog_get_content_area(GTK_DIALOG(dialog_));
 
   make_default_ = gtk_check_button_new_with_label(
       l10n_util::GetStringUTF8(IDS_FR_CUSTOMIZE_DEFAULT_BROWSER).c_str());
   gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(make_default_), TRUE);
   gtk_box_pack_start(GTK_BOX(content_area), make_default_, FALSE, FALSE, 0);
 
   report_crashes_ = gtk_check_button_new();
   GtkWidget* check_label = gtk_label_new(
       l10n_util::GetStringUTF8(IDS_OPTIONS_ENABLE_LOGGING).c_str());
   gtk_label_set_line_wrap(GTK_LABEL(check_label), TRUE);
@@ skipping 149 matching lines @@
 }
 
 void FirstRunDialog::FirstRunDone() {
   FirstRun::SetShowWelcomePagePref();
 
   if (dialog_)
     gtk_widget_destroy(dialog_);
   MessageLoop::current()->Quit();
   delete this;
 }