[mutter/wip/carlosg/there-can-be-only-one: 4/9] backends: Check for updates in the last used device after dispatching events

[Carlos Garnacho <carlosg src gnome org>]

commit ace9b03056c84a5bd33e9212ab156a27449cc3e4
Author: Carlos Garnacho <carlosg gnome org>
Date:   Thu Jan 13 14:02:26 2022 +0100

    backends: Check for updates in the last used device after dispatching events
    
    Instead of relying in the device being updated from different parts of our
    machinery for different backends, hook this up to our own event dispatching.
    This will allow dropping all other places where this is done.

 src/backends/meta-backend.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
---
diff --git a/src/backends/meta-backend.c b/src/backends/meta-backend.c
index ee947132fb..dea76ff7d8 100644
--- a/src/backends/meta-backend.c
+++ b/src/backends/meta-backend.c
@@ -1015,6 +1015,22 @@ system_bus_gotten_cb (GObject      *object,
                                         NULL);
 }
 
+static void
+update_last_device_from_event (MetaBackend  *backend,
+                               ClutterEvent *event)
+{
+  ClutterInputDevice *source;
+
+  /* Handled elsewhere */
+  if (event->type == CLUTTER_DEVICE_ADDED ||
+      event->type == CLUTTER_DEVICE_REMOVED)
+    return;
+
+  source = clutter_event_get_source_device (event);
+  if (source)
+    meta_backend_update_last_device (backend, source);
+}
+
 /* Mutter is responsible for pulling events off the X queue, so Clutter
  * doesn't need (and shouldn't) run its normal event source which polls
  * the X fd, but we do have to deal with dispatching events that accumulate
@@ -1054,6 +1070,7 @@ clutter_source_dispatch (GSource     *source,
       event->any.stage =
         CLUTTER_STAGE (meta_backend_get_stage (backend_source->backend));
       clutter_do_event (event);
+      update_last_device_from_event (backend_source->backend, event);
       clutter_event_free (event);
     }