diff -u b/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
--- b/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -2380,8 +2380,8 @@
     $test_info['test_run_id'] = $test_prefix;
     $test_info['in_child_site'] = TRUE;
 
-    $default_databases = settings()->get('databases.default');
-    foreach ($default_databases as &$value) {
+    $settings = settings()->getAll();
+    foreach ($settings['databases']['default'] as &$value) {
       // Extract the current default database prefix.
       if (!isset($value['prefix'])) {
         $current_prefix = '';
@@ -2398,6 +2398,7 @@
         'default' => $current_prefix . $test_prefix,
       );
     }
+    new Settings($settings);
   }
 }
 
only in patch2:
unchanged:
--- a/sites/default/default.settings.php
+++ b/sites/default/default.settings.php
@@ -55,7 +55,7 @@
 /**
  * Database settings:
  *
- * The $databases array specifies the database connection or
+ * The $settings['databases'] array specifies the database connection or
  * connections that Drupal may use.  Drupal is able to connect
  * to multiple databases, including multiple types of databases,
  * during the same request.
@@ -98,12 +98,12 @@
  * to a slave server when appropriate and if one is not available will simply
  * fall back to the single master server.
  *
- * The general format for the $databases array is as follows:
+ * The general format for the $settings['databases'] array is as follows:
  * @code
- * $databases['default']['default'] = $info_array;
- * $databases['default']['slave'][] = $info_array;
- * $databases['default']['slave'][] = $info_array;
- * $databases['extra']['default'] = $info_array;
+ * $settings['databases']['default']['default'] = $info_array;
+ * $settings['databases']['default']['slave'][] = $info_array;
+ * $settings['databases']['default']['slave'][] = $info_array;
+ * $settings['databases']['extra']['default'] = $info_array;
  * @endcode
  *
  * In the above example, $info_array is an array of settings described above.
@@ -115,7 +115,7 @@
  *
  * For a single database configuration, the following is sufficient:
  * @code
- * $databases['default']['default'] = array(
+ * $settings['databases']['default']['default'] = array(
  *   'driver' => 'mysql',
  *   'database' => 'databasename',
  *   'username' => 'username',
@@ -171,7 +171,7 @@
  * variable, and to reduce the database connection timeout to 5 seconds:
  *
  * @code
- * $databases['default']['default'] = array(
+ * $settings['databases']['default']['default'] = array(
  *   'init_commands' => array(
  *     'big_selects' => 'SET SQL_BIG_SELECTS=1',
  *   ),
@@ -190,7 +190,7 @@
  *
  * Database configuration format:
  * @code
- *   $databases['default']['default'] = array(
+ *   $settings['databases']['default']['default'] = array(
  *     'driver' => 'mysql',
  *     'database' => 'databasename',
  *     'username' => 'username',
@@ -198,7 +198,7 @@
  *     'host' => 'localhost',
  *     'prefix' => '',
  *   );
- *   $databases['default']['default'] = array(
+ *   $settings['databases']['default']['default'] = array(
  *     'driver' => 'pgsql',
  *     'database' => 'databasename',
  *     'username' => 'username',
@@ -206,13 +206,13 @@
  *     'host' => 'localhost',
  *     'prefix' => '',
  *   );
- *   $databases['default']['default'] = array(
+ *   $settings['databases']['default']['default'] = array(
  *     'driver' => 'sqlite',
  *     'database' => '/path/to/databasefilename',
  *   );
  * @endcode
  */
-$databases = array();
+$settings['databases'] = array();
 
 /**
  * Salt for one-time login links and cancel links, form tokens, etc.