commit 74df1e9a28f8508c9f5e1bb6c1e50daf2e9d9705
Author: Joel Pittet <joel@pittet.ca>
Date:   Mon Aug 3 21:56:28 2015 -0700

    docs

diff --git a/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
index 4be3e9e..b81860d 100644
--- a/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -514,10 +514,10 @@ function watchdog_exception($type, Exception $exception, $message = NULL, $varia
  * drupal_set_message(t('An error occurred and processing did not complete.'), 'error');
  * @endcode
  *
- * @param array|string $message
+ * @param string|array $message
  *   (optional) The translated message to be displayed to the user. For
  *   consistency with other messages, it should begin with a capital letter and
- *   end with a period or a render array.
+ *   end with a period. A render array may also be provided for markup.
  * @param string $type
  *   (optional) The message's type. Defaults to 'status'. These values are
  *   supported:
@@ -610,7 +610,9 @@ function drupal_get_messages($type = NULL, $clear_queue = TRUE) {
         // the messages also needs to be stored in the session. We retrieve the
         // safe status here and determine whether to mark the string as safe or
         // let autoescape do its thing. See drupal_set_message().
-        if ($message['safe']) { // Only set when the message is not an array.
+        // It's only nessasary to set the message as 'safe' when the message is
+        // not a renderable array.
+        if ($message['safe']) {
           $message['message'] = SafeMarkup::set($message['message']);
         }
         $messages[$message_type][$key] = $message['message'];