Index: trunk/src/wp-includes/plugin.php
===================================================================
--- trunk/src/wp-includes/plugin.php	(revision 53748)
+++ trunk/src/wp-includes/plugin.php	(revision 53770)
@@ -364,5 +364,5 @@
  * @global string[] $wp_current_filter Current filter.
  *
- * @param null|string $hook_name Optional. Filter hook to check. Defaults to null,
+ * @param string|null $hook_name Optional. Filter hook to check. Defaults to null,
  *                               which checks if any filter is currently being run.
  * @return bool Whether the filter is currently in the stack.