[gtkmm] Add Gtk::Entry::signal_activate()

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 24be4660b43bb450e00bef5099d83f2213e3ff39
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Wed May 11 14:23:58 2022 +0200

    Add Gtk::Entry::signal_activate()
    
    It's an action signal, but it can be used by applications.
    
    Fixes #100, see also #116.

 gtk/src/entry.hg | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/gtk/src/entry.hg b/gtk/src/entry.hg
index b5763fbe..3b2467ef 100644
--- a/gtk/src/entry.hg
+++ b/gtk/src/entry.hg
@@ -182,9 +182,12 @@ public:
   _WRAP_METHOD(Glib::RefPtr<Gio::MenuModel> get_extra_menu(), gtk_entry_get_extra_menu, refreturn)
   _WRAP_METHOD(Glib::RefPtr<const Gio::MenuModel> get_extra_menu() const, gtk_entry_get_extra_menu, 
refreturn, constversion)
 
-  _IGNORE_SIGNAL(activate)dnl // action signal
+  //TODO: Remove no_default_handler on "activate" when we can break ABI.
+  // "activate" is an action signal. Nevertheless it can be used by applications.
+  // https://gitlab.gnome.org/GNOME/gtk/-/issues/4848
+  // https://gitlab.gnome.org/GNOME/gtkmm/-/issues/100
+  _WRAP_SIGNAL(void activate(), "activate", no_default_handler, newin "4,8")
 
-#m4 _CONVERSION(`const GdkEventButton*',`const Glib::RefPtr<const 
Gdk::EventButton>&',`Glib::wrap(const_cast<GdkEventButton*>($3), true)')
   // no_default_handler because the wrapped C signals have no default handlers.
   _WRAP_SIGNAL(void icon_release(IconPosition icon_position), "icon-release", no_default_handler)
   _WRAP_SIGNAL(void icon_press(IconPosition icon_position), "icon-press", no_default_handler)