[grilo] core: annotate nullable error in callbacks

[Marc-Andre Lureau <malureau src gnome org>]

commit 49bf27d4deb8c1ed17995e7d9027875aebba04aa
Author: Marc-André Lureau <marcandre lureau gmail com>
Date:   Mon Nov 17 12:15:45 2014 +0100

    core: annotate nullable error in callbacks
    
    Since those arguments are optional error given to callbacks, annotate
    them as nullable.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=740186

 src/grl-source.h |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)
---
diff --git a/src/grl-source.h b/src/grl-source.h
index d91c481..7201f60 100644
--- a/src/grl-source.h
+++ b/src/grl-source.h
@@ -133,7 +133,7 @@ typedef enum {
  * @operation_id: operation identifier
  * @media: (transfer full): a data transfer object
  * @user_data: user data passed to grl_source_resolve()
- * @error: possible #GError generated at processing
+ * @error: (nullable): possible #GError generated at processing
  *
  * Prototype for the callback passed to grl_source_resolve()
  */
@@ -147,11 +147,11 @@ typedef void (*GrlSourceResolveCb) (GrlSource *source,
  * GrlSourceResultCb:
  * @source: a source
  * @operation_id: operation identifier
- * @media: (transfer full): a data transfer object
+ * @media: (nullable) (transfer full): a data transfer object
  * @remaining: the number of remaining #GrlMedia to process, or
  * GRL_SOURCE_REMAINING_UNKNOWN if it is unknown
  * @user_data: user data passed to the used method
- * @error: possible #GError generated at processing
+ * @error: (nullable): possible #GError generated at processing
  *
  * Prototype for the callback passed to the media sources' methods
  */
@@ -167,7 +167,7 @@ typedef void (*GrlSourceResultCb) (GrlSource *source,
  * @source: a source
  * @media: (transfer full): a data transfer object
  * @user_data: user data passed to grl_source_remove()
- * @error: possible #GError generated at processing
+ * @error: (nullable): possible #GError generated at processing
  *
  * Prototype for the callback passed to grl_source_remove()
  */
@@ -183,7 +183,7 @@ typedef void (*GrlSourceRemoveCb) (GrlSource *source,
  * @failed_keys: (element-type GrlKeyID) (transfer none): #GList of
  * keys that could not be updated, if any
  * @user_data: user data
- * @error: possible #GError generated
+ * @error: (nullable): possible #GError generated
  *
  * Prototype for the callback passed to grl_source_store_foo functions
  */