Issue #2905111 by bdlangton, joachim: error in docs for DrupalKernel::findSitePath()

core/lib/Drupal/Core/DrupalKernel.php

@@ -318,6 +318,9 @@ protected static function guessApplicationRoot() {
    * for bootstrap level configuration, file configuration stores, public file
    * storage and site specific modules and themes.
    *
+   * A file named sites.php must be present in the sites directory for
+   * multisite. If it doesn't exist, then 'sites/default' will be used.
+   *
    * Finds a matching site directory file by stripping the website's hostname
    * from left to right and pathname from right to left. By default, the
    * directory must contain a 'settings.php' file for it to match. If the
@@ -328,9 +331,8 @@ protected static function guessApplicationRoot() {
    * default.settings.php for examples on how the URL is converted to a
    * directory.
    *
-   * If a file named sites.php is present in the sites directory, it will be
-   * loaded prior to scanning for directories. That file can define aliases in
-   * an associative array named $sites. The array is written in the format
+   * The sites.php file in the sites directory can define aliases in an
+   * associative array named $sites. The array is written in the format
    * '<port>.<domain>.<path>' => 'directory'. As an example, to create a
    * directory alias for https://www.drupal.org:8080/mysite/test whose
    * configuration file is in sites/example.com, the array should be defined as: