diff --git a/core/includes/file.inc b/core/includes/file.inc
index 9319755bac8..f713d1f90f0 100644
--- a/core/includes/file.inc
+++ b/core/includes/file.inc
@@ -7,6 +7,7 @@
 
 use Drupal\Core\StreamWrapper\LocalStream;
 use Drupal\Component\PhpStorage\MTimeProtectedFastFileStorage;
+use Drupal\Core\StreamWrapper\PublicStream;
 
 /**
  * Stream wrapper bit flags that are the basis for composite types.
@@ -385,7 +386,7 @@ function file_stream_wrapper_get_instance_by_uri($uri) {
  * @param $scheme
  *   If the stream was "public://target", "public" would be the scheme.
  *
- * @return
+ * @return \Drupal\Core\StreamWrapper\StreamWrapperInterface
  *   Returns a new stream wrapper object appropriate for the given $scheme.
  *   For example, for the public scheme a stream wrapper object
  *   (Drupal\Core\StreamWrapper\PublicStream).
@@ -1614,7 +1615,7 @@ function file_directory_temp() {
 
     if (empty($temporary_directory)) {
       // If no directory has been found default to 'files/tmp'.
-      $temporary_directory = variable_get('file_public_path', conf_path() . '/files') . '/tmp';
+      $temporary_directory = PublicStream::basePath() . '/tmp';
 
       // Windows accepts paths with either slash (/) or backslash (\), but will
       // not accept a path which contains both a slash and a backslash. Since
diff --git a/core/lib/Drupal/Component/PhpStorage/PhpStorageFactory.php b/core/lib/Drupal/Component/PhpStorage/PhpStorageFactory.php
index c82cfcd7d02..15a7eb26b9d 100644
--- a/core/lib/Drupal/Component/PhpStorage/PhpStorageFactory.php
+++ b/core/lib/Drupal/Component/PhpStorage/PhpStorageFactory.php
@@ -6,6 +6,7 @@
  */
 
 namespace Drupal\Component\PhpStorage;
+use Drupal\Core\StreamWrapper\PublicStream;
 
 /**
  * Creates a php storage object
@@ -49,8 +50,7 @@ class PhpStorageFactory {
       $configuration['bin'] = $name;
     }
     if (!isset($configuration['directory'])) {
-      $path = isset($conf['file_public_path']) ? $conf['file_public_path'] : conf_path() . '/files';
-      $configuration['directory'] = DRUPAL_ROOT . "/$path/php";
+      $configuration['directory'] = DRUPAL_ROOT . '/' . PublicStream::basePath() . '/php';
     }
     return new $class($configuration);
   }
diff --git a/core/lib/Drupal/Core/StreamWrapper/PublicStream.php b/core/lib/Drupal/Core/StreamWrapper/PublicStream.php
index 207b77a5b65..94f551406e4 100644
--- a/core/lib/Drupal/Core/StreamWrapper/PublicStream.php
+++ b/core/lib/Drupal/Core/StreamWrapper/PublicStream.php
@@ -16,20 +16,36 @@ namespace Drupal\Core\StreamWrapper;
 class PublicStream extends LocalStream {
 
   /**
-   * Implements Drupal\Core\StreamWrapper\LocalStream::getDirectoryPath()
+   * {@inheritdoc}
    */
   public function getDirectoryPath() {
-    return variable_get('file_public_path', conf_path() . '/files');
+    return static::basePath();
   }
 
   /**
-   * Implements Drupal\Core\StreamWrapper\StreamWrapperInterface::getExternalUrl().
-   *
-   * @return string
-   *   Returns the HTML URI of a public file.
+   * {@inheritdoc}
    */
-  function getExternalUrl() {
+  public function getExternalUrl() {
     $path = str_replace('\\', '/', $this->getTarget());
     return $GLOBALS['base_url'] . '/' . self::getDirectoryPath() . '/' . drupal_encode_path($path);
   }
+
+  /**
+   * Returns the base path for public://.
+   *
+   * @return string
+   *   The base path for public:// typically sites/default/files.
+   */
+  public static function basePath() {
+    $base_path = settings()->get('file_public_path', conf_path() . '/files');
+    if ($test_prefix = drupal_valid_test_ua()) {
+      // Append the testing suffix unless already given.
+      // @see Drupal\simpletest\WebTestBase::setUp()
+      if (strpos($base_path, '/simpletest/' . substr($test_prefix, 10)) === FALSE) {
+        return $base_path . '/simpletest/' . substr($test_prefix, 10);
+      }
+    }
+    return $base_path;
+  }
+
 }
diff --git a/core/modules/filter/lib/Drupal/filter/Tests/FilterHtmlImageSecureTest.php b/core/modules/filter/lib/Drupal/filter/Tests/FilterHtmlImageSecureTest.php
index 548eb8ea2e9..bea3e82f03d 100644
--- a/core/modules/filter/lib/Drupal/filter/Tests/FilterHtmlImageSecureTest.php
+++ b/core/modules/filter/lib/Drupal/filter/Tests/FilterHtmlImageSecureTest.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\filter\Tests;
 
+use Drupal\Core\StreamWrapper\PublicStream;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -75,7 +76,7 @@ class FilterHtmlImageSecureTest extends WebTestBase {
   function testImageSource() {
     global $base_url;
 
-    $public_files_path = variable_get('file_public_path', conf_path() . '/files');
+    $public_files_path = PublicStream::basePath();
 
     $http_base_url = preg_replace('/^https?/', 'http', $base_url);
     $https_base_url = preg_replace('/^https?/', 'https', $base_url);
diff --git a/core/modules/image/image.module b/core/modules/image/image.module
index 03b8c95b5e3..fa03dcd9a37 100644
--- a/core/modules/image/image.module
+++ b/core/modules/image/image.module
@@ -226,25 +226,6 @@ function image_permission() {
   );
 }
 
-/**
- * Implements hook_form_FORM_ID_alter().
- */
-function image_form_system_file_system_settings_alter(&$form, &$form_state) {
-  $form['#submit'][] = 'image_system_file_system_settings_submit';
-}
-
-/**
- * Form submission handler for system_file_system_settings().
- *
- * Adds a menu rebuild after the public file path has been changed, so that the
- * menu router item depending on that file path will be regenerated.
- */
-function image_system_file_system_settings_submit($form, &$form_state) {
-  if ($form['file_public_path']['#default_value'] !== $form_state['values']['file_public_path']) {
-    Drupal::state()->set('menu_rebuild_needed', TRUE);
-  }
-}
-
 /**
  * Implements hook_file_download().
  *
diff --git a/core/modules/locale/lib/Drupal/locale/Tests/LocaleUpdateBase.php b/core/modules/locale/lib/Drupal/locale/Tests/LocaleUpdateBase.php
index 46d082ee1d8..3e185dff372 100644
--- a/core/modules/locale/lib/Drupal/locale/Tests/LocaleUpdateBase.php
+++ b/core/modules/locale/lib/Drupal/locale/Tests/LocaleUpdateBase.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\locale\Tests;
 
+use Drupal\Core\StreamWrapper\PublicStream;
 use Drupal\simpletest\WebTestBase;
 use Drupal\Component\Utility\String;
 
@@ -172,7 +173,7 @@ EOF;
     \Drupal::state()->set('locale.test_projects_alter', TRUE);
 
     // Setup the environment.
-    $public_path = variable_get('file_public_path', conf_path() . '/files');
+    $public_path = PublicStream::basePath();
     $this->setTranslationsDirectory($public_path . '/local');
     $config->set('translation.default_filename', '%project-%version.%language._po')->save();
 
diff --git a/core/modules/locale/tests/modules/locale_test/locale_test.module b/core/modules/locale/tests/modules/locale_test/locale_test.module
index 1ba430c26be..973a27b7291 100644
--- a/core/modules/locale/tests/modules/locale_test/locale_test.module
+++ b/core/modules/locale/tests/modules/locale_test/locale_test.module
@@ -4,6 +4,7 @@
  * @file
  * Simulate a custom module with a local po file.
  */
+use Drupal\Core\StreamWrapper\PublicStream;
 
 /**
  * Implements hook_system_info_alter().
@@ -42,7 +43,7 @@ function locale_test_locale_translation_projects_alter(&$projects) {
     // Instead of the default ftp.drupal.org we use the file system of the test
     // instance to simulate a remote file location.
     $url = url(NULL, array('absolute' => TRUE));
-    $remote_url = $url . variable_get('file_public_path', conf_path() . '/files') . '/remote/';
+    $remote_url = $url . PublicStream::basePath() . '/remote/';
 
     // Completely replace the project data with a set of test projects.
     $base_url = url();
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
index 04e98f16899..0805bc1e93c 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
@@ -17,6 +17,7 @@ use Drupal\Core\Database\ConnectionNotDefinedException;
 use Drupal\Core\Config\StorageInterface;
 use Drupal\Core\DrupalKernel;
 use Drupal\Core\Language\Language;
+use Drupal\Core\StreamWrapper\PublicStream;
 use ReflectionMethod;
 use ReflectionObject;
 
@@ -708,7 +709,7 @@ abstract class TestBase {
     if ($simpletest_config->get('verbose')) {
       // Initialize verbose debugging.
       $this->verbose = TRUE;
-      $this->verboseDirectory = variable_get('file_public_path', conf_path() . '/files') . '/simpletest/verbose';
+      $this->verboseDirectory = PublicStream::basePath() . '/simpletest/verbose';
       $this->verboseDirectoryUrl = file_create_url($this->verboseDirectory);
       if (file_prepare_directory($this->verboseDirectory, FILE_CREATE_DIRECTORY) && !file_exists($this->verboseDirectory . '/.htaccess')) {
         file_put_contents($this->verboseDirectory . '/.htaccess', "<IfModule mod_expires.c>\nExpiresActive Off\n</IfModule>\n");
@@ -888,7 +889,9 @@ abstract class TestBase {
     $this->originalTheme = isset($GLOBALS['theme']) ? $GLOBALS['theme'] : NULL;
 
     // Save further contextual information.
-    $this->originalFileDirectory = variable_get('file_public_path', conf_path() . '/files');
+    // Use the original files directory to avoid nesting it within an existing
+    // simpletest directory if a test is executed within a test.
+    $this->originalFileDirectory = settings()->get('file_public_path', conf_path() . '/files');
     $this->originalProfile = drupal_get_profile();
     $this->originalUser = isset($user) ? clone $user : NULL;
 
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/UnitTestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/UnitTestBase.php
index c990234e38d..dd725ed8026 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/UnitTestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/UnitTestBase.php
@@ -56,7 +56,7 @@ abstract class UnitTestBase extends TestBase {
     $conf = array();
     drupal_static_reset();
 
-    $conf['file_public_path'] = $this->public_files_directory;
+    $this->settingsSet('file_public_path', $this->public_files_directory);
 
     // Change the database prefix.
     // All static variables need to be reset before the database prefix is
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
index 4aec435b42a..9e1ecb8ac2d 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
@@ -16,6 +16,7 @@ use Drupal\Core\Database\ConnectionNotDefinedException;
 use Drupal\Core\Language\Language;
 use Drupal\Core\Session\AccountInterface;
 use Drupal\Core\Session\UserSession;
+use Drupal\Core\StreamWrapper\PublicStream;
 use PDO;
 use stdClass;
 use DOMDocument;
@@ -416,7 +417,7 @@ abstract class WebTestBase extends TestBase {
       $original = drupal_get_path('module', 'simpletest') . '/files';
       $files = file_scan_directory($original, '/(html|image|javascript|php|sql)-.*/');
       foreach ($files as $file) {
-        file_unmanaged_copy($file->uri, variable_get('file_public_path', conf_path() . '/files'));
+        file_unmanaged_copy($file->uri, PublicStream::basePath());
       }
 
       $this->generatedTestFiles = TRUE;
@@ -772,7 +773,7 @@ abstract class WebTestBase extends TestBase {
         NestedArray::setValue($GLOBALS['conf'], array_merge(array($config_base), explode('.', $name)), $value);
       }
     }
-    $GLOBALS['conf']['file_public_path'] = $this->public_files_directory;
+    $this->settingsSet('file_public_path', $this->public_files_directory);
     // Execute the non-interactive installer.
     require_once DRUPAL_ROOT . '/core/includes/install.core.inc';
     $this->settingsSet('cache', array('default' => 'cache.backend.memory'));
@@ -820,7 +821,6 @@ abstract class WebTestBase extends TestBase {
       }
       $config->save();
     }
-    variable_set('file_public_path', $this->public_files_directory);
 
     // Use the test mail class instead of the default mail handler class.
     \Drupal::config('system.mail')->set('interface.default', 'Drupal\Core\Mail\VariableLog')->save();
diff --git a/core/modules/system/lib/Drupal/system/Form/FileSystemForm.php b/core/modules/system/lib/Drupal/system/Form/FileSystemForm.php
index 3a4aa18fc46..83cb9e7e49c 100644
--- a/core/modules/system/lib/Drupal/system/Form/FileSystemForm.php
+++ b/core/modules/system/lib/Drupal/system/Form/FileSystemForm.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\system\Form;
 
+use Drupal\Core\StreamWrapper\PublicStream;
 use Drupal\system\SystemConfigFormBase;
 
 /**
@@ -27,12 +28,11 @@ class FileSystemForm extends SystemConfigFormBase {
   public function buildForm(array $form, array &$form_state) {
     $config = $this->configFactory->get('system.file');
     $form['file_public_path'] = array(
-      '#type' => 'textfield',
+      '#type' => 'item',
       '#title' => t('Public file system path'),
-      '#default_value' => variable_get('file_public_path', conf_path() . '/files'),
-      '#maxlength' => 255,
-      '#description' => t('A local file system path where public files will be stored. This directory must exist and be writable by Drupal. This directory must be relative to the Drupal installation directory and be accessible over the web.'),
-      '#after_build' => array('system_check_directory'),
+      '#default_value' => PublicStream::basePath(),
+      '#markup' => PublicStream::basePath(),
+      '#description' => t('A local file system path where public files will be stored. This directory must exist and be writable by Drupal. This directory must be relative to the Drupal installation directory and be accessible over the web. This must be changed in settings.php'),
     );
 
     $form['file_private_path'] = array(
@@ -78,7 +78,6 @@ class FileSystemForm extends SystemConfigFormBase {
     $config = $this->configFactory->get('system.file')
       ->set('path.private', $form_state['values']['file_private_path'])
       ->set('path.temporary', $form_state['values']['file_temporary_path']);
-    variable_set('file_public_path', $form_state['values']['file_public_path']);
 
     if (isset($form_state['values']['file_default_scheme'])) {
       $config->set('default_scheme', $form_state['values']['file_default_scheme']);
diff --git a/core/modules/system/lib/Drupal/system/Form/ThemeSettingsForm.php b/core/modules/system/lib/Drupal/system/Form/ThemeSettingsForm.php
index 216d0d19902..c77b391a527 100644
--- a/core/modules/system/lib/Drupal/system/Form/ThemeSettingsForm.php
+++ b/core/modules/system/lib/Drupal/system/Form/ThemeSettingsForm.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\system\Form;
 
+use Drupal\Core\StreamWrapper\PublicStream;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 use Drupal\Core\Cache\Cache;
@@ -240,7 +241,7 @@ class ThemeSettingsForm extends SystemConfigFormBase {
 
         // Prepare local file path for description.
         if ($original_path && isset($friendly_path)) {
-          $local_file = strtr($original_path, array('public:/' => variable_get('file_public_path', conf_path() . '/files')));
+          $local_file = strtr($original_path, array('public:/' => PublicStream::basePath()));
         }
         elseif ($theme_name) {
           $local_file = drupal_get_path('theme', $theme_name) . '/' . $default;
diff --git a/core/modules/system/lib/Drupal/system/Tests/File/ConfigTest.php b/core/modules/system/lib/Drupal/system/Tests/File/ConfigTest.php
index 73143659d62..36de9d99ba9 100644
--- a/core/modules/system/lib/Drupal/system/Tests/File/ConfigTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/File/ConfigTest.php
@@ -37,7 +37,6 @@ class ConfigTest extends FileTestBase {
     // upon form submission.
     $file_path = $this->public_files_directory;
     $fields = array(
-      'file_public_path' => $file_path . '/file_config_page_test/public',
       'file_private_path' => $file_path . '/file_config_page_test/private',
       'file_temporary_path' => $file_path . '/file_config_page_test/temporary',
       'file_default_scheme' => 'private',
diff --git a/core/modules/system/lib/Drupal/system/Tests/File/StreamWrapperTest.php b/core/modules/system/lib/Drupal/system/Tests/File/StreamWrapperTest.php
index 1b5c42901be..16bc59221a6 100644
--- a/core/modules/system/lib/Drupal/system/Tests/File/StreamWrapperTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/File/StreamWrapperTest.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\system\Tests\File;
 
+use Drupal\Core\StreamWrapper\PublicStream;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -82,7 +83,7 @@ class StreamWrapperTest extends WebTestBase {
     // Test file_build_uri() and
     // Drupal\Core\StreamWrapper\LocalStream::getDirectoryPath().
     $this->assertEqual(file_build_uri('foo/bar.txt'), 'public://foo/bar.txt', 'Expected scheme was added.');
-    $this->assertEqual(file_stream_wrapper_get_instance_by_scheme('public')->getDirectoryPath(), variable_get('file_public_path'), 'Expected default directory path was returned.');
+    $this->assertEqual(file_stream_wrapper_get_instance_by_scheme('public')->getDirectoryPath(), PublicStream::basePath(), 'Expected default directory path was returned.');
     $this->assertEqual(file_stream_wrapper_get_instance_by_scheme('temporary')->getDirectoryPath(), $config->get('path.temporary'), 'Expected temporary directory path was returned.');
     $config->set('default_scheme', 'private')->save();
     $this->assertEqual(file_build_uri('foo/bar.txt'), 'private://foo/bar.txt', 'Got a valid URI from foo/bar.txt.');
diff --git a/core/modules/system/lib/Drupal/system/Tests/FileTransfer/FileTransferTest.php b/core/modules/system/lib/Drupal/system/Tests/FileTransfer/FileTransferTest.php
index 080e8fd5d23..066f8541356 100644
--- a/core/modules/system/lib/Drupal/system/Tests/FileTransfer/FileTransferTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/FileTransfer/FileTransferTest.php
@@ -8,6 +8,7 @@
 namespace Drupal\system\Tests\FileTransfer;
 
 use Drupal\Core\FileTransfer\FileTransferException;
+use Drupal\Core\StreamWrapper\PublicStream;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -91,7 +92,7 @@ class FileTransferTest extends WebTestBase {
 
     $gotit = TRUE;
     try {
-      $this->testConnection->copyDirectory($source, DRUPAL_ROOT . '/'. variable_get('file_public_path', conf_path() . '/files'));
+      $this->testConnection->copyDirectory($source, DRUPAL_ROOT . '/' . PublicStream::basePath());
     }
     catch (FileTransferException $e) {
       $gotit = FALSE;
diff --git a/core/modules/system/lib/Drupal/system/Tests/System/ThemeTest.php b/core/modules/system/lib/Drupal/system/Tests/System/ThemeTest.php
index 4358f10a4fe..4d5aec1a805 100644
--- a/core/modules/system/lib/Drupal/system/Tests/System/ThemeTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/System/ThemeTest.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\system\Tests\System;
 
+use Drupal\Core\StreamWrapper\PublicStream;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -45,7 +46,7 @@ class ThemeTest extends WebTestBase {
   function testThemeSettings() {
     // Specify a filesystem path to be used for the logo.
     $file = current($this->drupalGetTestFiles('image'));
-    $file_relative = strtr($file->uri, array('public:/' => variable_get('file_public_path', conf_path() . '/files')));
+    $file_relative = strtr($file->uri, array('public:/' => PublicStream::basePath()));
     $default_theme_path = 'core/themes/stark';
 
     $supported_paths = array(
@@ -97,7 +98,7 @@ class ThemeTest extends WebTestBase {
       if (file_uri_scheme($input) == 'public') {
         $implicit_public_file = file_uri_target($input);
         $explicit_file = $input;
-        $local_file = strtr($input, array('public:/' => variable_get('file_public_path', conf_path() . '/files')));
+        $local_file = strtr($input, array('public:/' => PublicStream::basePath()));
       }
       // Adjust for fully qualified stream wrapper URI elsewhere.
       elseif (file_uri_scheme($input) !== FALSE) {
@@ -107,7 +108,7 @@ class ThemeTest extends WebTestBase {
       elseif ($input == file_uri_target($file->uri)) {
         $implicit_public_file = $input;
         $explicit_file = 'public://' . $input;
-        $local_file = variable_get('file_public_path', conf_path() . '/files') . '/' . $input;
+        $local_file = PublicStream::basePath() . '/' . $input;
       }
       $this->assertEqual((string) $elements[0], $implicit_public_file);
       $this->assertEqual((string) $elements[1], $explicit_file);
@@ -134,9 +135,9 @@ class ThemeTest extends WebTestBase {
       // Relative path within the public filesystem to non-existing file.
       'whatever.png',
       // Relative path to non-existing file in public filesystem.
-      variable_get('file_public_path', conf_path() . '/files') . '/whatever.png',
+      PublicStream::basePath() . '/whatever.png',
       // Semi-absolute path to non-existing file in public filesystem.
-      '/' . variable_get('file_public_path', conf_path() . '/files') . '/whatever.png',
+      '/' . PublicStream::basePath() . '/whatever.png',
       // Relative path to arbitrary non-existing file.
       'core/misc/whatever.png',
       // Semi-absolute path to arbitrary non-existing file.
diff --git a/core/modules/system/system.install b/core/modules/system/system.install
index 3f0fac01fed..a4e79269f92 100644
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
@@ -9,6 +9,7 @@ use Drupal\Component\Utility\Crypt;
 use Drupal\Component\Uuid\Uuid;
 use Drupal\Core\Database\Database;
 use Drupal\Core\Language\Language;
+use Drupal\Core\StreamWrapper\PublicStream;
 
 /**
  * Implements hook_requirements().
@@ -302,7 +303,7 @@ function system_requirements($phase) {
   if ($phase != 'install') {
     $filesystem_config = Drupal::config('system.file');
     $directories = array(
-      variable_get('file_public_path', conf_path() . '/files'),
+      PublicStream::basePath(),
       // By default no private files directory is configured. For private files
       // to be secure the admin needs to provide a path outside the webroot.
       $filesystem_config->get('path.private'),
@@ -315,8 +316,8 @@ function system_requirements($phase) {
   if ($phase == 'install') {
     global $conf;
     $directories = array();
-    if (!empty($conf['file_public_path'])) {
-      $directories[] = $conf['file_public_path'];
+    if ($file_public_path = settings()->get('file_public_path')) {
+      $directories[] = $file_public_path;
     }
     else {
       // If we are installing Drupal, the settings.php file might not exist yet
@@ -2241,6 +2242,15 @@ function system_update_8059() {
   ));
 }
 
+/**
+ * Move the file_public_path variable to settings.
+ */
+function system_upgrade_8060() {
+  if ($path = update_variable_get('file_public_path')) {
+    drupal_rewrite_settings(array('settings' => array('file_public_path' => $path)));
+  }
+}
+
 /**
  * @} End of "defgroup updates-7.x-to-8.x".
  * The next series of updates should start at 9000.
diff --git a/core/scripts/run-tests.sh b/core/scripts/run-tests.sh
index 091af6ca9ff..31a9c89dfcf 100755
--- a/core/scripts/run-tests.sh
+++ b/core/scripts/run-tests.sh
@@ -3,6 +3,7 @@
  * @file
  * This script runs Drupal tests from command line.
  */
+use Drupal\Core\StreamWrapper\PublicStream;
 
 const SIMPLETEST_SCRIPT_COLOR_PASS = 32; // Green.
 const SIMPLETEST_SCRIPT_COLOR_FAIL = 31; // Red.
@@ -399,7 +400,7 @@ function simpletest_script_execute_batch($test_classes) {
           echo 'FATAL ' . $child['class'] . ': test runner returned a non-zero error code (' . $status['exitcode'] . ').' . "\n";
           if ($args['die-on-fail']) {
             list($db_prefix, ) = simpletest_last_test_get($child['test_id']);
-            $public_files = variable_get('file_public_path', conf_path() . '/files');
+            $public_files = PublicStream::basePath();
             $test_directory = $public_files . '/simpletest/' . substr($db_prefix, 10);
             echo 'Simpletest database and files kept and test exited immediately on fail so should be reproducible if you change settings.php to use the database prefix '. $db_prefix . ' and config directories in '. $test_directory . "\n";
             $args['keep-results'] = TRUE;
@@ -568,7 +569,7 @@ function simpletest_script_cleanup($test_id, $test_class, $exitcode) {
 
   // Check whether a test file directory was setup already.
   // @see prepareEnvironment()
-  $public_files = variable_get('file_public_path', conf_path() . '/files');
+  $public_files = PublicStream::basePath();
   $test_directory = $public_files . '/simpletest/' . substr($db_prefix, 10);
   if (is_dir($test_directory)) {
     // Output the error_log.
diff --git a/sites/default/default.settings.php b/sites/default/default.settings.php
index fe16cfcf464..a11647d5064 100644
--- a/sites/default/default.settings.php
+++ b/sites/default/default.settings.php
@@ -454,6 +454,15 @@ $settings['update_free_access'] = FALSE;
  */
 # $settings['mixed_mode_sessions'] = TRUE;
 
+/**
+ * Public file path:
+ *
+ * A local file system path where public files will be stored. This directory
+ * must exist and be writable by Drupal. This directory must be relative to
+ * the Drupal installation directory and be accessible over the web.
+ */
+# $settings['file_public_path'] = 'sites/default/files';
+
 /**
  * Session write interval:
  *