[mutter/wip/carlosg/grabs-pt1: 7/16] clutter: Propagate events only inside the grab

[Carlos Garnacho <carlosg src gnome org>]

commit 65fc23165256701795c7adc2a0d8b91f1b9d65b4
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed Oct 27 00:13:35 2021 +0200

    clutter: Propagate events only inside the grab
    
    The grab actor becomes the "root" of the events being handled, events
    inside propagate normally, but become silenced when falling outside
    the grab area.

 clutter/clutter/clutter-main.c          |  4 +++-
 clutter/clutter/clutter-stage-private.h |  1 +
 clutter/clutter/clutter-stage.c         | 12 ++++++++++++
 3 files changed, 16 insertions(+), 1 deletion(-)
---
diff --git a/clutter/clutter/clutter-main.c b/clutter/clutter/clutter-main.c
index 9dc010b415..98f64eeb6e 100644
--- a/clutter/clutter/clutter-main.c
+++ b/clutter/clutter/clutter-main.c
@@ -683,7 +683,9 @@ emit_event_chain (ClutterEvent *event)
       return;
     }
 
-  _clutter_actor_handle_event (event->any.source, NULL, event);
+  _clutter_actor_handle_event (event->any.source,
+                               clutter_stage_get_grab_actor (event->any.stage),
+                               event);
 }
 
 /*
diff --git a/clutter/clutter/clutter-stage-private.h b/clutter/clutter/clutter-stage-private.h
index e5e1c81fa4..6ce68d4623 100644
--- a/clutter/clutter/clutter-stage-private.h
+++ b/clutter/clutter/clutter-stage-private.h
@@ -133,6 +133,7 @@ void clutter_stage_set_actor_needs_immediate_relayout (ClutterStage *stage);
 void clutter_stage_remove_device_entry (ClutterStage         *self,
                                         ClutterInputDevice   *device,
                                         ClutterEventSequence *sequence);
+ClutterActor * clutter_stage_get_grab_actor (ClutterStage *stage);
 
 G_END_DECLS
 
diff --git a/clutter/clutter/clutter-stage.c b/clutter/clutter/clutter-stage.c
index d6ab02b787..8224179073 100644
--- a/clutter/clutter/clutter-stage.c
+++ b/clutter/clutter/clutter-stage.c
@@ -3726,3 +3726,15 @@ clutter_ungrab (ClutterStage *stage,
 
   g_free (grab);
 }
+
+ClutterActor *
+clutter_stage_get_grab_actor (ClutterStage *stage)
+{
+  ClutterStagePrivate *priv = stage->priv;
+
+  if (!priv->grabs)
+    return NULL;
+
+  /* Return active grab */
+  return priv->grabs->actor;
+}