clutter/actor: Make frame clock picking semi private API

Let's not expose that outside of mutter quite yet; it's not used in
gnome-shell, and to avoid future breakage if it starts to be used, lets
move it to clutter-mutter.h so only mutter and clutter itself can use
it.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1404

clutter/clutter/clutter-actor.c

@@ -16354,7 +16354,7 @@ clutter_actor_is_effectively_on_stage_view (ClutterActor     *self,
 }
 
 /**
- * clutter_actor_pick_frame_clock:
+ * clutter_actor_pick_frame_clock: (skip)
  * @self: a #ClutterActor
  *
  * Pick the most suitable frame clock for driving animations for this actor.

clutter/clutter/clutter-actor.h

@@ -935,9 +935,6 @@ GList * clutter_actor_peek_stage_views (ClutterActor *self);
 CLUTTER_EXPORT
 void clutter_actor_invalidate_transform (ClutterActor *self);
 
-CLUTTER_EXPORT
-ClutterFrameClock * clutter_actor_pick_frame_clock (ClutterActor *self);
-
 G_END_DECLS
 
 #endif /* __CLUTTER_ACTOR_H__ */

clutter/clutter/clutter-mutter.h

@@ -68,6 +68,9 @@ gboolean clutter_actor_has_damage (ClutterActor *actor);
 CLUTTER_EXPORT
 gboolean clutter_actor_has_transitions (ClutterActor *actor);
 
+CLUTTER_EXPORT
+ClutterFrameClock * clutter_actor_pick_frame_clock (ClutterActor *self);
+
 #undef __CLUTTER_H_INSIDE__
 
 #endif /* __CLUTTER_MUTTER_H__ */

clutter/clutter/clutter-timeline.c

@@ -103,6 +103,7 @@
 #include "clutter-frame-clock.h"
 #include "clutter-main.h"
 #include "clutter-marshal.h"
+#include "clutter-mutter.h"
 #include "clutter-private.h"
 #include "clutter-scriptable.h"
 #include "clutter-timeline-private.h"