[libgit2-glib] ggit-tree-builder.c: Fix return annotations

[Igor Gnatenko <ignatenko src gnome org>]

commit e8c014fad3e3e8fa24fe1bb708485b0362048280
Author: Brian C. Lane <bcl redhat com>
Date:   Wed Aug 30 18:18:34 2017 -0700

    ggit-tree-builder.c: Fix return annotations
    
    Add (nullable) as needed.

 libgit2-glib/ggit-tree-builder.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/libgit2-glib/ggit-tree-builder.c b/libgit2-glib/ggit-tree-builder.c
index 2f04dc6..58f4c6f 100644
--- a/libgit2-glib/ggit-tree-builder.c
+++ b/libgit2-glib/ggit-tree-builder.c
@@ -132,7 +132,7 @@ ggit_tree_builder_remove (GgitTreeBuilder  *builder,
  *
  * Get an entry by path.
  *
- * Returns: the #GGitTreeEntry or %NULL if no such entry exists.
+ * Returns: (transfer full) (nullable): the #GGitTreeEntry or %NULL if no such entry exists.
  *
  */
 GgitTreeEntry *
@@ -179,7 +179,7 @@ ggit_tree_builder_clear (GgitTreeBuilder *builder)
  *
  * Write the contents of the tree builder as a tree object.
  *
- * Returns: the #GgitOId of the created tree object.
+ * Returns: (transfer full) (nullable): the #GgitOId of the created tree object or %NULL.
  *
  **/
 GgitOId *
@@ -219,7 +219,7 @@ ggit_tree_builder_write (GgitTreeBuilder  *builder,
  * Note that the returned #GgitTreeEntry is bound to the lifetime of the tree
  * builder and cannot be used after the tree builder has been freed.
  *
- * Returns: (transfer full): a #GgitTreeEntry.
+ * Returns: (transfer full) (nullable): a #GgitTreeEntry or %NULL.
  *
  **/
 GgitTreeEntry *