service-channel: Add global shotcuts portal backend client type

The global shortcuts portal backend component lives in
gnome-control-center, and is responsible for preseting the GUI for
managing client provided global shortcuts.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4173>

data/dbus-interfaces/org.gnome.Mutter.ServiceChannel.xml

@@ -9,6 +9,7 @@
         ServiceClientTypes:
            PORTAL_BACKEND: 1
            FILECHOOSER_PORTAL_BACKEND: 2
+           GLOBAL_SHORTCUTS_PORTAL_BACKEND: 3
     -->
     <method name="OpenWaylandServiceConnection">
       <arg name="service_client_type" type="u" direction="in" />

src/core/meta-service-channel.c

@@ -99,6 +99,7 @@ verify_service_client_type (uint32_t service_client_type)
       return FALSE;
     case META_SERVICE_CLIENT_TYPE_PORTAL_BACKEND:
     case META_SERVICE_CLIENT_TYPE_FILECHOOSER_PORTAL_BACKEND:
+    case META_SERVICE_CLIENT_TYPE_GLOBAL_SHORTCUTS_PORTAL_BACKEND:
       return TRUE;
     }
 

src/core/meta-service-channel.h

@@ -31,6 +31,7 @@ typedef enum _MetaServiceClientType
   META_SERVICE_CLIENT_TYPE_NONE,
   META_SERVICE_CLIENT_TYPE_PORTAL_BACKEND,
   META_SERVICE_CLIENT_TYPE_FILECHOOSER_PORTAL_BACKEND,
+  META_SERVICE_CLIENT_TYPE_GLOBAL_SHORTCUTS_PORTAL_BACKEND,
 } MetaServiceClientType;
 
 #define META_TYPE_SERVICE_CHANNEL (meta_service_channel_get_type ())

src/wayland/meta-wayland-x11-interop.c

@@ -99,6 +99,7 @@ x11_interop_filter (const struct wl_client *client,
   MetaServiceClientType allowed_client_types[] = {
     META_SERVICE_CLIENT_TYPE_PORTAL_BACKEND,
     META_SERVICE_CLIENT_TYPE_FILECHOOSER_PORTAL_BACKEND,
+    META_SERVICE_CLIENT_TYPE_GLOBAL_SHORTCUTS_PORTAL_BACKEND,
   };
   size_t i;