[clutter] actor: Clarify that add_effect() sinks floating references on the effect

[Philip Withnall <pwithnall src gnome org>]

commit d7372cc45347b92effd1bf2c0f60185a1e35ab27
Author: Philip Withnall <philip withnall collabora co uk>
Date:   Tue Jul 12 14:48:58 2016 +0100

    actor: Clarify that add_effect() sinks floating references on the effect
    
    So if you want to reuse a ClutterEffect, make sure to
    g_object_ref_sink() it yourself first.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=768734

 clutter/clutter-actor.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)
---
diff --git a/clutter/clutter-actor.c b/clutter/clutter-actor.c
index fedcbfe..f7cbc93 100644
--- a/clutter/clutter-actor.c
+++ b/clutter/clutter-actor.c
@@ -17162,6 +17162,9 @@ clutter_actor_get_clip_to_allocation (ClutterActor *self)
  * clutter_actor_remove_effect() or clutter_actor_clear_effects() is
  * called.
  *
+ * Note that as #ClutterEffect is initially unowned,
+ * clutter_actor_add_effect() will sink any floating reference on @effect.
+ *
  * Since: 1.4
  */
 void
@@ -17185,7 +17188,11 @@ clutter_actor_add_effect (ClutterActor  *self,
  * @effect: a #ClutterEffect
  *
  * A convenience function for setting the name of a #ClutterEffect
- * while adding it to the list of effectss applied to @self
+ * while adding it to the list of effects applied to @self.
+ *
+ * Note that as #ClutterEffect is initially unowned,
+ * clutter_actor_add_effect_with_name() will sink any floating
+ * reference on @effect.
  *
  * This function is the logical equivalent of:
  *