[gnome-builder] tree: add ide_tree_node_is_root()

[Christian Hergert <chergert src gnome org>]

commit 29b41e9a31ad5c7609c163701967dcb227de3e6b
Author: Christian Hergert <chergert redhat com>
Date:   Sat Jul 2 01:10:43 2016 -0700

    tree: add ide_tree_node_is_root()

 libide/tree/ide-tree-node.c |    8 ++++++++
 libide/tree/ide-tree-node.h |    1 +
 2 files changed, 9 insertions(+), 0 deletions(-)
---
diff --git a/libide/tree/ide-tree-node.c b/libide/tree/ide-tree-node.c
index f1d63d8..1923791 100644
--- a/libide/tree/ide-tree-node.c
+++ b/libide/tree/ide-tree-node.c
@@ -976,3 +976,11 @@ ide_tree_node_set_use_dim_label (IdeTreeNode *self,
       g_object_notify_by_pspec (G_OBJECT (self), properties [PROP_USE_DIM_LABEL]);
     }
 }
+
+gboolean
+ide_tree_node_is_root (IdeTreeNode *node)
+{
+  g_return_val_if_fail (IDE_IS_TREE_NODE (node), FALSE);
+
+  return node->parent == NULL;
+}
diff --git a/libide/tree/ide-tree-node.h b/libide/tree/ide-tree-node.h
index 7fd255b..ebafaee 100644
--- a/libide/tree/ide-tree-node.h
+++ b/libide/tree/ide-tree-node.h
@@ -30,6 +30,7 @@ void            ide_tree_node_insert_sorted         (IdeTreeNode            *nod
                                                      IdeTreeNode            *child,
                                                      IdeTreeNodeCompareFunc  compare_func,
                                                      gpointer                user_data);
+gboolean        ide_tree_node_is_root               (IdeTreeNode            *node);
 const gchar    *ide_tree_node_get_icon_name         (IdeTreeNode            *node);
 GObject        *ide_tree_node_get_item              (IdeTreeNode            *node);
 IdeTreeNode    *ide_tree_node_get_parent            (IdeTreeNode            *node);