[gtk+] overlay: Document availability of properties

[Matthias Clasen <matthiasc src gnome org>]

commit 5993117b848afed45b5b812720cb5993d4873b6c
Author: Pavel Grunt <pgrunt redhat com>
Date:   Mon Oct 17 10:32:04 2016 +0200

    overlay: Document availability of properties
    
    Add missing "Since"
    
    https://bugzilla.gnome.org/show_bug.cgi?id=773082

 gtk/gtkoverlay.c |   17 +++++++++++++++++
 1 files changed, 17 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkoverlay.c b/gtk/gtkoverlay.c
index 9f5ad93..2c35b9e 100644
--- a/gtk/gtkoverlay.c
+++ b/gtk/gtkoverlay.c
@@ -541,6 +541,8 @@ gtk_overlay_remove (GtkContainer *container,
  * A widget’s index in the @overlay children list determines which order
  * the children are drawn if they overlap. The first child is drawn at
  * the bottom. It also affects the default focus chain order.
+ *
+ * Since: 3.18
  */
 void
 gtk_overlay_reorder_overlay (GtkOverlay *overlay,
@@ -765,10 +767,25 @@ gtk_overlay_class_init (GtkOverlayClass *klass)
 
   klass->get_child_position = gtk_overlay_get_child_position;
 
+  /**
+   * GtkOverlay:pass-through:
+   *
+   * Pass through input, does not affect main child.
+   *
+   * Since: 3.18
+   */
   gtk_container_class_install_child_property (container_class, CHILD_PROP_PASS_THROUGH,
       g_param_spec_boolean ("pass-through", P_("Pass Through"), P_("Pass through input, does not affect main 
child"),
                             FALSE,
                             GTK_PARAM_READWRITE));
+
+  /**
+   * GtkOverlay:index:
+   *
+   * The index of the overlay in the parent, -1 for the main child.
+   *
+   * Since: 3.18
+   */
   gtk_container_class_install_child_property (container_class, CHILD_PROP_INDEX,
                                              g_param_spec_int ("index",
                                                                P_("Index"),