[grilo/0.2.x] pls: annotate that filter_func can be NULL

[Bastien Nocera <hadess src gnome org>]

commit 0b5e0a709b4b4e362cd369b21f35ddb61821a819
Author: Xavier Claessens <xavier claessens collabora com>
Date:   Tue Sep 22 13:54:20 2015 -0400

    pls: annotate that filter_func can be NULL
    
    https://bugzilla.gnome.org/show_bug.cgi?id=755433

 libs/pls/grl-pls.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/libs/pls/grl-pls.c b/libs/pls/grl-pls.c
index 8f353b0..bf395a3 100644
--- a/libs/pls/grl-pls.c
+++ b/libs/pls/grl-pls.c
@@ -773,7 +773,7 @@ multiple_result_async_cb (GrlSource *source,
 /**
  * grl_pls_browse_by_spec:
  * @source: a source
- * @filter_func: (scope async): A filter function, or %NULL
+ * @filter_func: (scope async) (allow-none): A filter function, or %NULL
  * @bs: a GrlSourceBrowseSpec structure with details of the browsing operation
  *
  * Browse into a playlist. The playlist entries are
@@ -878,7 +878,7 @@ grl_pls_browse_by_spec (GrlSource *source,
  * @keys: (element-type GrlKeyID): the #GList of
  * #GrlKeyID<!-- -->s to request
  * @options: options wanted for that operation
- * @filter_func: (scope async): A filter function, or %NULL
+ * @filter_func: (scope async) (allow-none): A filter function, or %NULL
  * @callback: (scope notified): the user defined callback
  * @user_data: the user data to pass in the callback
  *
@@ -948,7 +948,7 @@ grl_pls_browse (GrlSource *source,
  * @playlist: a playlist
  * @keys: (element-type GrlKeyID): the #GList of
  * #GrlKeyID<!-- -->s to request
- * @filter_func: (scope async): A filter function, or %NULL
+ * @filter_func: (scope async) (allow-none): A filter function, or %NULL
  * @options: options wanted for that operation
  * @error: a #GError, or @NULL
  *