[gnote] Replace std::string by Glib::ustring PreferencesDialog

[Aurimas ÄŒernius <aurimasc src gnome org>]

commit 39869c667dcac536a073acfa5dcb13698b2f0e43
Author: Aurimas ÄŒernius <aurisc4 gmail com>
Date:   Sun Feb 5 22:02:16 2017 +0200

    Replace std::string by Glib::ustring PreferencesDialog

 src/preferencesdialog.cpp  |    2 +-
 src/preferencetabaddin.hpp |    6 ++----
 2 files changed, 3 insertions(+), 5 deletions(-)
---
diff --git a/src/preferencesdialog.cpp b/src/preferencesdialog.cpp
index 63d5bd6..7ca55fd 100644
--- a/src/preferencesdialog.cpp
+++ b/src/preferencesdialog.cpp
@@ -132,7 +132,7 @@ namespace gnote {
       DBG_OUT("Adding preference tab addin: %s", 
               typeid(*tabAddin).name());
         try {
-          std::string tabName;
+          Glib::ustring tabName;
           Gtk::Widget *tabWidget = NULL;
           if (tabAddin->get_preference_tab_widget (this, tabName, tabWidget)) {
             notebook->append_page (*manage(tabWidget), tabName);
diff --git a/src/preferencetabaddin.hpp b/src/preferencetabaddin.hpp
index b959b74..25d461d 100644
--- a/src/preferencetabaddin.hpp
+++ b/src/preferencetabaddin.hpp
@@ -1,7 +1,7 @@
 /*
  * gnote
  *
- * Copyright (C) 2013 Aurimas Cernius
+ * Copyright (C) 2013,2017 Aurimas Cernius
  * Copyright (C) 2009 Hubert Figuiere
  *
  * This program is free software: you can redistribute it and/or modify
@@ -24,8 +24,6 @@
 #ifndef _PREFERENCE_TAB_ADDIN_HPP_
 #define _PREFERENCE_TAB_ADDIN_HPP_
 
-#include <string>
-
 #include <gtkmm/widget.h>
 
 #include "abstractaddin.hpp"
@@ -59,7 +57,7 @@ namespace gnote {
   public:
     virtual bool get_preference_tab_widget (
                   Gtk::Dialog * parent,
-                  std::string  & tabLabel,
+                  Glib::ustring & tabLabel,
                   Gtk::Widget * preferenceWidget) = 0;
   };