[gtk/wip/matthiasc/shortcut-4: 138/139] shortcutmanager: Add some more docs

[Matthias Clasen <matthiasc src gnome org>]

commit 26d469134240b7083a0be0ca6ad6b920e15ccd3e
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Mar 25 17:13:37 2020 -0400

    shortcutmanager: Add some more docs

 gtk/gtkshortcutmanager.c | 7 +++++++
 1 file changed, 7 insertions(+)
---
diff --git a/gtk/gtkshortcutmanager.c b/gtk/gtkshortcutmanager.c
index 71a1b35eb1..c6530c0efe 100644
--- a/gtk/gtkshortcutmanager.c
+++ b/gtk/gtkshortcutmanager.c
@@ -30,6 +30,13 @@
  *
  * The GtkShortcutManager interface is used to implement
  * shortcut scopes.
+ *
+ * This is important for #GtkNative widgets that have their own surface,
+ * since the event controllers that are used to implement managed and
+ * global scopes are limited to the same native.
+ *
+ * Examples for widgets implementing #GtkShortcutManager are #GtkWindow
+ * and #GtkPopover.
  */
 
 G_DEFINE_INTERFACE (GtkShortcutManager, gtk_shortcut_manager, G_TYPE_OBJECT)