Gtk3: Silence deprecation warnings in //remoting

remoting/host/it2me/it2me_confirmation_dialog_linux.cc

 // Copyright 2016 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 <gtk/gtk.h>
 
 #include <memory>
 #include <string>
 
 #include "base/bind.h"
@@ skipping 106 matching lines @@
   GtkWidget* content_area =
       gtk_dialog_get_content_area(GTK_DIALOG(confirmation_window_));
 
   base::string16 dialog_text =
       base::i18n::MessageFormatter::FormatWithNumberedArgs(
           l10n_util::GetStringUTF16(
               IDS_SHARE_CONFIRM_DIALOG_MESSAGE_WITH_USERNAME),
           remote_user_email);
   GtkWidget* text_label = gtk_label_new(base::UTF16ToUTF8(dialog_text).c_str());
   gtk_label_set_line_wrap(GTK_LABEL(text_label), true);
+  G_GNUC_BEGIN_IGNORE_DEPRECATIONS;
   gtk_misc_set_padding(GTK_MISC(text_label), 12, 12);
+  G_GNUC_END_IGNORE_DEPRECATIONS;
 
   gtk_container_add(GTK_CONTAINER(content_area), text_label);
   gtk_widget_show_all(content_area);
 
   gtk_window_set_urgency_hint(GTK_WINDOW(confirmation_window_), true);
   gtk_window_present(GTK_WINDOW(confirmation_window_));
 }
 
 void It2MeConfirmationDialogLinux::OnResponse(GtkDialog* dialog,
                                               int response_id) {
   DCHECK(result_callback_);
 
   Hide();
   base::ResetAndReturn(&result_callback_).Run(
       (response_id == GTK_RESPONSE_OK) ? Result::OK : Result::CANCEL);
 }
 
 }  // namespace
 
 // static
 std::unique_ptr<It2MeConfirmationDialog> It2MeConfirmationDialog::Create() {
   return base::MakeUnique<It2MeConfirmationDialogLinux>();
 }
 
 }  // namespace remoting