notification: Use categories from xdg desktop notification spec

The xdg spec¹ uses slightly different names thus making it hard for apps
to use API like `g_notification_set_category` in a way that works for
portaled and non-portaled use cases.

It also makes things slighlty more consistent as the current call.*
sub-categories (`.incoming`, `.ongoing`) indicate a state while the `im`
category indicates a type (`message`).

1) https://specifications.freedesktop.org/notification-spec/1.2/categories.html

Signed-off-by: Guido Günther <[email protected]>

src/notification.c

@@ -889,11 +889,11 @@ parse_category (GVariantBuilder  *builder,
 {
   const char *category;
   const char *supported_categories[] = {
-    "im.message",
+    "im.received",
     "alarm.ringing",
     "call.incoming",
     "call.ongoing",
-    "call.missed",
+    "call.unanswered",
     "weather.warning.extreme",
     "cellbroadcast.danger.extreme",
     "cellbroadcast.danger.severe",

tests/notification.c

@@ -515,7 +515,7 @@ test_notification_category (void)
 
   notification_s = "{ 'title': <'test notification 5'>, "
                    "  'body': <'test notification body 5'>, "
-                   "  'category': <'im.message'>"
+                   "  'category': <'im.received'>"
                    "}";
 
   run_notification_test ("test5", notification_s, NULL, FALSE);