De-duplicate "actor contains actor" code

Add _st_actor_contains() in st-private for use within St, and
monkey-patch in a Clutter.Actor.contains() for use by javascript, and
then replace all the duplicate implementations with one or the other
of those.

https://bugzilla.gnome.org/show_bug.cgi?id=621197

src/st/st-clickable.c

@@ -11,6 +11,8 @@
 
 #include "st-clickable.h"
 
+#include "st-private.h"
+
 G_DEFINE_TYPE (StClickable, st_clickable, ST_TYPE_BIN);
 
 struct _StClickablePrivate {
@@ -69,17 +71,6 @@ set_pressed (StClickable  *self,
   g_object_notify (G_OBJECT (self), "pressed");
 }
 
-static gboolean
-st_clickable_contains (StClickable     *self,
-                       ClutterActor    *actor)
-{
-  while (actor != NULL && actor != (ClutterActor*)self)
-    {
-      actor = clutter_actor_get_parent (actor);
-    }
-  return actor != NULL;
-}
-
 static gboolean
 st_clickable_enter_event (ClutterActor         *actor,
                           ClutterCrossingEvent *event)
@@ -130,7 +121,7 @@ st_clickable_button_press_event (ClutterActor       *actor,
   if (self->priv->held)
     return TRUE;
 
-  if (!st_clickable_contains (self, event->source))
+  if (!_st_actor_contains (actor, event->source))
     return FALSE;
 
   self->priv->held = TRUE;
@@ -157,7 +148,7 @@ st_clickable_button_release_event (ClutterActor       *actor,
   self->priv->held = FALSE;
   clutter_ungrab_pointer ();
 
-  if (!st_clickable_contains (self, event->source))
+  if (!_st_actor_contains (actor, event->source))
     return FALSE;
 
   set_pressed (self, FALSE);

src/st/st-entry.c

@@ -65,6 +65,7 @@
 #include "st-texture-cache.h"
 #include "st-marshal.h"
 #include "st-clipboard.h"
+#include "st-private.h"
 
 #define HAS_FOCUS(actor) (clutter_actor_get_stage (actor) && clutter_stage_get_key_focus ((ClutterStage *) clutter_actor_get_stage (actor)) == actor)
 
@@ -577,22 +578,13 @@ st_entry_key_focus_in (ClutterActor *actor)
   clutter_actor_grab_key_focus (priv->entry);
 }
 
-static gboolean
-actor_contains (ClutterActor *widget,
-                ClutterActor *other)
-{
-  while (other != NULL && other != widget)
-    other = clutter_actor_get_parent (other);
-  return other != NULL;
-}
-
 static gboolean
 st_entry_enter_event (ClutterActor         *actor,
                       ClutterCrossingEvent *event)
 {
   StEntryPrivate *priv = ST_ENTRY_PRIV (actor);
 
-  if (actor_contains (actor, event->source)
+  if (_st_actor_contains (actor, event->source)
       && priv->hint && priv->hint_visible)
     {
       st_widget_set_hover (ST_WIDGET (actor), TRUE);
@@ -605,7 +597,7 @@ static gboolean
 st_entry_leave_event (ClutterActor         *actor,
                       ClutterCrossingEvent *event)
 {
-  if (!actor_contains (actor, event->related))
+  if (!_st_actor_contains (actor, event->related))
     st_widget_set_hover (ST_WIDGET (actor), FALSE);
 
   return CLUTTER_ACTOR_CLASS (st_entry_parent_class)->leave_event (actor, event);

src/st/st-private.c

@@ -310,3 +310,12 @@ _st_set_text_from_style (ClutterText *text,
 
   pango_attr_list_unref (attribs);
 }
+
+gboolean
+_st_actor_contains (ClutterActor *actor,
+                    ClutterActor *child)
+{
+  while (child != NULL && child != actor)
+    child = clutter_actor_get_parent (child);
+  return child != NULL;
+}

src/st/st-private.h

@@ -72,4 +72,7 @@ void _st_allocate_fill (StWidget        *parent,
 void _st_set_text_from_style (ClutterText *text,
                               StThemeNode *theme_node);
 
+gboolean _st_actor_contains (ClutterActor *actor,
+                             ClutterActor *child);
+
 #endif /* __ST_PRIVATE_H__ */

src/st/st-widget.c

@@ -557,15 +557,6 @@ st_widget_get_theme_node (StWidget *widget)
   return priv->theme_node;
 }
 
-static gboolean
-actor_contains (ClutterActor *widget,
-                ClutterActor *other)
-{
-  while (other != NULL && other != widget)
-    other = clutter_actor_get_parent (other);
-  return other != NULL;
-}
-
 static gboolean
 st_widget_enter (ClutterActor         *actor,
                  ClutterCrossingEvent *event)
@@ -574,7 +565,7 @@ st_widget_enter (ClutterActor         *actor,
 
   if (priv->track_hover)
     {
-      if (actor_contains (actor, event->source))
+      if (_st_actor_contains (actor, event->source))
         st_widget_set_hover (ST_WIDGET (actor), TRUE);
       else
         {
@@ -600,7 +591,7 @@ st_widget_leave (ClutterActor         *actor,
 
   if (priv->track_hover)
     {
-      if (!actor_contains (actor, event->related))
+      if (!_st_actor_contains (actor, event->related))
         st_widget_set_hover (ST_WIDGET (actor), FALSE);
     }
 
@@ -1589,17 +1580,13 @@ st_widget_sync_hover (StWidget *widget)
 {
   ClutterDeviceManager *device_manager;
   ClutterInputDevice *pointer;
-  ClutterActor *actor;
+  ClutterActor *pointer_actor;
 
   device_manager = clutter_device_manager_get_default ();
   pointer = clutter_device_manager_get_core_device (device_manager,
                                                     CLUTTER_POINTER_DEVICE);
-  actor = clutter_input_device_get_pointer_actor (pointer);
-
-  while (actor && actor != (ClutterActor *)widget)
-    actor = clutter_actor_get_parent (actor);
-
-  st_widget_set_hover (widget, actor == (ClutterActor *)widget);
+  pointer_actor = clutter_input_device_get_pointer_actor (pointer);
+  st_widget_set_hover (widget, _st_actor_contains (CLUTTER_ACTOR (widget), pointer_actor));
 }
 
 /**