[glom] Db_AddDel: Use std::unique_ptr<> for the menu, instead of new and delete.

[Murray Cumming <murrayc src gnome org>]

commit b32655d13c87f3ea4152411e7eef3440a84e9d13
Author: Murray Cumming <murrayc murrayc com>
Date:   Fri Feb 5 10:23:37 2016 +0100

    Db_AddDel: Use std::unique_ptr<> for the menu, instead of new and delete.
    
    I am not very happy with passing the raw pointer to gtkmm's
    attach_to_widget(), but that seems to be the normal use of
    unique_ptr<>::operator*() and unique_ptr<>::get(),
    as long as we don't expect the receiving API to take any
    ownership.

 glom/mode_data/db_adddel/db_adddel.cc |    3 +--
 glom/mode_data/db_adddel/db_adddel.h  |    2 +-
 2 files changed, 2 insertions(+), 3 deletions(-)
---
diff --git a/glom/mode_data/db_adddel/db_adddel.cc b/glom/mode_data/db_adddel/db_adddel.cc
index 26f1f2d..6b266e6 100644
--- a/glom/mode_data/db_adddel/db_adddel.cc
+++ b/glom/mode_data/db_adddel/db_adddel.cc
@@ -46,7 +46,6 @@ DbAddDel::DbAddDel()
   m_column_is_sorted(false),
   m_column_sorted_direction(false),
   m_column_sorted(0),
-  m_pMenuPopup(nullptr),
   m_bAllowUserActions(true),
   m_bPreventUserSignals(false),
   m_bIgnoreTreeViewSignals(false),
@@ -260,7 +259,7 @@ void DbAddDel::setup_menu(Gtk::Widget* /* widget */)
   menu->append(_("_Layout"), "context.layout");
 #endif
 
-  m_pMenuPopup = new Gtk::Menu(menu);
+  m_pMenuPopup = std::make_unique<Gtk::Menu>(menu);
   m_pMenuPopup->attach_to_widget(*this);
 
   if(get_allow_user_actions())
diff --git a/glom/mode_data/db_adddel/db_adddel.h b/glom/mode_data/db_adddel/db_adddel.h
index 54eccf4..3861ba5 100644
--- a/glom/mode_data/db_adddel/db_adddel.h
+++ b/glom/mode_data/db_adddel/db_adddel.h
@@ -402,7 +402,7 @@ protected:
 
 private:
   //TODO: Avoid repeating these in so many widgets:
-  Gtk::Menu* m_pMenuPopup;
+  std::unique_ptr<Gtk::Menu> m_pMenuPopup;
   Glib::RefPtr<Gio::SimpleActionGroup> m_refActionGroup;
   Glib::RefPtr<Gio::SimpleAction> m_refContextEdit, m_refContextAdd, m_refContextDelete;