Add g_file_info_has_namespace

Need this to quickly see if we should set attributes from
this GFileInfo in metadata extension.

gio/gfileinfo.c

@@ -484,6 +484,42 @@ g_file_info_has_attribute (GFileInfo  *info,
   return value != NULL;
 }
 
+/**
+ * g_file_info_has_namespace:
+ * @info: a #GFileInfo.
+ * @name_space: a file attribute namespace.
+ *
+ * Checks if a file info structure has an attribute in the
+ * specified @name_space.
+ *
+ * Returns: %TRUE if @Ginfo has an attribute in @name_space,
+ *     %FALSE otherwise.
+ *
+ * Since: 2.22
+ **/
+gboolean
+g_file_info_has_namespace (GFileInfo  *info,
+			   const char *name_space)
+{
+  GFileAttribute *attrs;
+  guint32 ns_id;
+  int i;
+
+  g_return_val_if_fail (G_IS_FILE_INFO (info), FALSE);
+  g_return_val_if_fail (name_space != NULL, FALSE);
+
+  ns_id = lookup_namespace (name_space);
+
+  attrs = (GFileAttribute *)info->attributes->data;
+  for (i = 0; i < info->attributes->len; i++)
+    {
+      if (GET_NS (attrs[i].attribute) == ns_id)
+	return TRUE;
+    }
+
+  return FALSE;
+}
+
 /**
  * g_file_info_list_attributes:
  * @info: a #GFileInfo.

gio/gfileinfo.h

@@ -749,6 +749,8 @@ void               g_file_info_copy_into                 (GFileInfo  *src_info,
 							  GFileInfo  *dest_info);
 gboolean           g_file_info_has_attribute             (GFileInfo  *info,
 							  const char *attribute);
+gboolean           g_file_info_has_namespace             (GFileInfo  *info,
+							  const char *name_space);
 char **            g_file_info_list_attributes           (GFileInfo  *info,
 							  const char *name_space);
 gboolean           g_file_info_get_attribute_data        (GFileInfo  *info,

gio/gio.symbols

@@ -377,6 +377,7 @@ g_file_info_new
 g_file_info_dup 
 g_file_info_copy_into 
 g_file_info_has_attribute 
+g_file_info_has_namespace
 g_file_info_list_attributes 
 g_file_info_get_attribute_type 
 g_file_info_remove_attribute