[niepce] ui: add Delete shortcut for delete

[Hubert Figuière <hub src gnome org>]

commit f592bfda4734fc672d6e9c809820b2d6c12c3599
Author: Hubert Figuière <hub figuiere net>
Date:   Fri Jun 2 23:27:41 2017 -0400

    ui: add Delete shortcut for delete

 src/niepce/ui/niepcewindow.cpp |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/niepce/ui/niepcewindow.cpp b/src/niepce/ui/niepcewindow.cpp
index 9802318..5f5bf26 100644
--- a/src/niepce/ui/niepcewindow.cpp
+++ b/src/niepce/ui/niepcewindow.cpp
@@ -232,7 +232,7 @@ void NiepceWindow::init_actions()
     fwk::add_action(m_action_group,
                     "Delete",
                     sigc::mem_fun(*this, &NiepceWindow::on_action_edit_delete),
-                    section, _("Delete"), "win", nullptr);
+                    section, _("Delete"), "win", "Delete");
 
     submenu = Gio::Menu::create();
     m_menu->append_submenu(_("Tools"), submenu);