[gtk+] Use g_return_val_if_fail where return value needed.

[Jasper St. Pierre <jstpierre src gnome org>]

commit 4d41903548408e0c8507f3ba79dcac59d14bc0f7
Author: Daniel Svensson <dsvensson gmail com>
Date:   Sun Oct 27 22:36:32 2013 +0100

    Use g_return_val_if_fail where return value needed.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=710987

 gtk/gtkactionmuxer.c |    4 ++--
 gtk/gtkapplication.c |    4 ++--
 gtk/gtkbuilder.c     |    2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)
---
diff --git a/gtk/gtkactionmuxer.c b/gtk/gtkactionmuxer.c
index 3588fa2..1537864 100644
--- a/gtk/gtkactionmuxer.c
+++ b/gtk/gtkactionmuxer.c
@@ -887,8 +887,8 @@ gtk_print_action_and_target (const gchar *action_namespace,
 {
   GString *result;
 
-  g_return_if_fail (strchr (action_name, '|') == NULL);
-  g_return_if_fail (action_namespace == NULL || strchr (action_namespace, '|') == NULL);
+  g_return_val_if_fail (strchr (action_name, '|') == NULL, NULL);
+  g_return_val_if_fail (action_namespace == NULL || strchr (action_namespace, '|') == NULL, NULL);
 
   result = g_string_new (NULL);
 
diff --git a/gtk/gtkapplication.c b/gtk/gtkapplication.c
index ccd49ec..d8af4a0 100644
--- a/gtk/gtkapplication.c
+++ b/gtk/gtkapplication.c
@@ -2170,8 +2170,8 @@ gtk_application_get_accels_for_action (GtkApplication *application,
   gchar *action_and_target;
   gchar **accels;
 
-  g_return_if_fail (GTK_IS_APPLICATION (application));
-  g_return_if_fail (detailed_action_name != NULL);
+  g_return_val_if_fail (GTK_IS_APPLICATION (application), NULL);
+  g_return_val_if_fail (detailed_action_name != NULL, NULL);
 
   action_and_target = normalise_detailed_name (detailed_action_name);
   accels = accels_get_accels_for_action (&application->priv->accels, action_and_target);
diff --git a/gtk/gtkbuilder.c b/gtk/gtkbuilder.c
index b76931e..c6b6b25 100644
--- a/gtk/gtkbuilder.c
+++ b/gtk/gtkbuilder.c
@@ -2568,7 +2568,7 @@ gtk_builder_set_application (GtkBuilder     *builder,
 GtkApplication *
 gtk_builder_get_application (GtkBuilder *builder)
 {
-  g_return_if_fail (GTK_IS_BUILDER (builder));
+  g_return_val_if_fail (GTK_IS_BUILDER (builder), NULL);
 
   if (!builder->priv->application)
     {