[libdazzle] asan: plug a few more leaks detected by asan

[Christian Hergert <chergert src gnome org>]

commit b44973e6f8c48352af2b70af2ef5356e4b2db97c
Author: Christian Hergert <chergert redhat com>
Date:   Wed Dec 13 22:17:02 2017 -0800

    asan: plug a few more leaks detected by asan

 src/panel/dzl-dock-widget.c |    4 ++--
 src/util/dzl-gtk.c          |    2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/src/panel/dzl-dock-widget.c b/src/panel/dzl-dock-widget.c
index e22e6ca..c8e0c68 100644
--- a/src/panel/dzl-dock-widget.c
+++ b/src/panel/dzl-dock-widget.c
@@ -139,7 +139,7 @@ dzl_dock_widget_get_property (GObject    *object,
       break;
 
     case PROP_ICON_NAME:
-      g_value_set_string (value, dzl_dock_widget_item_get_icon_name (DZL_DOCK_ITEM (self)));
+      g_value_take_string (value, dzl_dock_widget_item_get_icon_name (DZL_DOCK_ITEM (self)));
       break;
 
     case PROP_MANAGER:
@@ -147,7 +147,7 @@ dzl_dock_widget_get_property (GObject    *object,
       break;
 
     case PROP_TITLE:
-      g_value_set_string (value, dzl_dock_widget_item_get_title (DZL_DOCK_ITEM (self)));
+      g_value_take_string (value, dzl_dock_widget_item_get_title (DZL_DOCK_ITEM (self)));
       break;
 
     default:
diff --git a/src/util/dzl-gtk.c b/src/util/dzl-gtk.c
index b289cad..dd0edb6 100644
--- a/src/util/dzl-gtk.c
+++ b/src/util/dzl-gtk.c
@@ -408,7 +408,7 @@ dzl_gtk_widget_mux_action_groups (GtkWidget   *widget,
                                   const gchar *mux_key)
 {
   const gchar * const *old_prefixes = NULL;
-  const gchar **prefixes = NULL;
+  g_autofree const gchar **prefixes = NULL;
 
   g_return_if_fail (GTK_IS_WIDGET (widget));
   g_return_if_fail (!from_widget || GTK_IS_WIDGET (from_widget));