[mutter] clutter: Ensure we always call handle_event_post for processed events

[Marge Bot <marge-bot src gnome org>]

commit 012c0a18efbb3a694de2e72af4948bc1ea03cbeb
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Wed Mar 10 01:13:34 2021 +0100

    clutter: Ensure we always call handle_event_post for processed events
    
    Since commit 2ceac4a device-related X11 events aren't processed anymore,
    causing the input settings not to handle the devices.
    This is due to the fact that we may never call clutter_seat_handle_event_post()
    for such events.
    
    While this is always happening for the native backend, it doesn't happen in
    X11 because the events are removed from the queue as part of
    meta_x11_handle_event(), and thus no event was queued to the stage by the
    backend events source.
    
    This also makes sure that the event post handler is called after the
    event is actually processed, and not before an event is queued.
    
    Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1564
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1769>

 clutter/clutter/clutter-main.c | 3 +++
 src/backends/meta-backend.c    | 5 -----
 2 files changed, 3 insertions(+), 5 deletions(-)
---
diff --git a/clutter/clutter/clutter-main.c b/clutter/clutter/clutter-main.c
index 4b7b141e77..dd2198ccaa 100644
--- a/clutter/clutter/clutter-main.c
+++ b/clutter/clutter/clutter-main.c
@@ -1894,8 +1894,10 @@ _clutter_process_event (ClutterEvent *event)
 {
   ClutterMainContext *context;
   ClutterActor *stage;
+  ClutterSeat *seat;
 
   context = _clutter_context_get_default ();
+  seat = clutter_backend_get_default_seat (context->backend);
 
   stage = CLUTTER_ACTOR (event->any.stage);
   if (stage == NULL)
@@ -1911,6 +1913,7 @@ _clutter_process_event (ClutterEvent *event)
   context->current_event = g_slist_prepend (context->current_event, event);
 
   _clutter_process_event_details (stage, context, event);
+  clutter_seat_handle_event_post (seat, event);
 
   context->current_event = g_slist_delete_link (context->current_event, context->current_event);
 }
diff --git a/src/backends/meta-backend.c b/src/backends/meta-backend.c
index 0788cf1025..9e525957e0 100644
--- a/src/backends/meta-backend.c
+++ b/src/backends/meta-backend.c
@@ -991,17 +991,12 @@ clutter_source_dispatch (GSource     *source,
                          gpointer     user_data)
 {
   MetaBackendSource *backend_source = (MetaBackendSource *) source;
-  MetaBackendPrivate *priv =
-    meta_backend_get_instance_private (backend_source->backend);
   ClutterEvent *event = clutter_event_get ();
-  ClutterSeat *seat;
 
   if (event)
     {
       event->any.stage =
         CLUTTER_STAGE (meta_backend_get_stage (backend_source->backend));
-      seat = clutter_backend_get_default_seat (priv->clutter_backend);
-      clutter_seat_handle_event_post (seat, event);
       clutter_do_event (event);
       clutter_event_free (event);
     }