[gtk/matthiasc/for-master] button: Add explicit key bindings for activation

[Matthias Clasen <matthiasc src gnome org>]

commit 7b76be53606fe909160d853e49bb1c41bfa93e71
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Jul 18 12:51:18 2020 -0400

    button: Add explicit key bindings for activation
    
    We should not rely on GtkWindow to have global
    "activate-default" key bindings that happen to
    fall back to activating the focus widget. This is
    unreliable, since the bubbling up from the button
    to the toplevel may run across other widgets that
    may want to use Enter for their own purpose, and
    then the button loses out. By adding our own
    key bindings, the button gets to handle it before
    its ancestors.
    
    This fixes check buttons in the inspector property
    list not reacting to Enter despite having focus.

 gtk/gtkbutton.c | 11 +++++++++++
 1 file changed, 11 insertions(+)
---
diff --git a/gtk/gtkbutton.c b/gtk/gtkbutton.c
index 8a0c084b52..2cb79cc483 100644
--- a/gtk/gtkbutton.c
+++ b/gtk/gtkbutton.c
@@ -294,6 +294,17 @@ gtk_button_class_init (GtkButtonClass *klass)
   gtk_widget_class_set_layout_manager_type (widget_class, GTK_TYPE_BIN_LAYOUT);
   gtk_widget_class_set_accessible_type (widget_class, GTK_TYPE_BUTTON_ACCESSIBLE);
   gtk_widget_class_set_css_name (widget_class, I_("button"));
+
+  gtk_widget_class_add_binding_signal (widget_class, GDK_KEY_space, 0,
+                                       "activate", NULL);
+  gtk_widget_class_add_binding_signal (widget_class, GDK_KEY_KP_Space, 0,
+                                       "activate", NULL);
+  gtk_widget_class_add_binding_signal (widget_class, GDK_KEY_Return, 0,
+                                       "activate", NULL);
+  gtk_widget_class_add_binding_signal (widget_class, GDK_KEY_ISO_Enter, 0,
+                                       "activate", NULL);
+  gtk_widget_class_add_binding_signal (widget_class, GDK_KEY_KP_Enter, 0,
+                                       "activate", NULL);
 }
 
 static void