diff --git a/core/lib/Drupal/Core/CoreServiceProvider.php b/core/lib/Drupal/Core/CoreServiceProvider.php
index 4a3d748..7e02c80 100644
--- a/core/lib/Drupal/Core/CoreServiceProvider.php
+++ b/core/lib/Drupal/Core/CoreServiceProvider.php
@@ -136,7 +136,7 @@ protected function registerTest(ContainerBuilder $container) {
     }
     // Add the HTTP request middleware to Guzzle.
     $container
-      ->register('test.http_client.middleware', 'Drupal\Core\Test\EventSubscriber\TestHttpClientMiddleware')
+      ->register('test.http_client.middleware', 'Drupal\Core\Test\HttpClientMiddleware\TestHttpClientMiddleware')
       ->addTag('http_client_middleware');
   }
 
diff --git a/core/lib/Drupal/Core/Http/ClientFactory.php b/core/lib/Drupal/Core/Http/ClientFactory.php
index 2bcd56a..7524e89 100644
--- a/core/lib/Drupal/Core/Http/ClientFactory.php
+++ b/core/lib/Drupal/Core/Http/ClientFactory.php
@@ -59,9 +59,6 @@ public function fromOptions(array $config = []) {
       'handler' => $this->stack,
     ];
 
-    // The entire config array is merged/configurable to allow Guzzle client
-    // options outside of 'defaults' to be changed, such as 'adapter', or
-    // 'message_factory'.
     $config = NestedArray::mergeDeep($default_config, Settings::get('http_client_config', []), $config);
 
     return new Client($config);
diff --git a/core/lib/Drupal/Core/Http/HandlerStackConfigurator.php b/core/lib/Drupal/Core/Http/HandlerStackConfigurator.php
index 4b9657d..54e4bd9 100644
--- a/core/lib/Drupal/Core/Http/HandlerStackConfigurator.php
+++ b/core/lib/Drupal/Core/Http/HandlerStackConfigurator.php
@@ -22,7 +22,7 @@
  * @see https://guzzle.readthedocs.org/en/latest/handlers-and-middleware.html
  *
  * @see \Drupal\Core\Http\Client
- * @see \Drupal\Core\Test\EventSubscriber\HttpRequestSubscriber
+ * @see \Drupal\Core\Test\HttpClientMiddleware\TestHttpClientMiddleware
  */
 class HandlerStackConfigurator {
 
diff --git a/core/lib/Drupal/Core/Test/EventSubscriber/TestHttpClientMiddleware.php b/core/lib/Drupal/Core/Test/HttpClientMiddleware/TestHttpClientMiddleware.php
similarity index 90%
rename from core/lib/Drupal/Core/Test/EventSubscriber/TestHttpClientMiddleware.php
rename to core/lib/Drupal/Core/Test/HttpClientMiddleware/TestHttpClientMiddleware.php
index 0f1a8fa..1488189 100644
--- a/core/lib/Drupal/Core/Test/EventSubscriber/TestHttpClientMiddleware.php
+++ b/core/lib/Drupal/Core/Test/HttpClientMiddleware/TestHttpClientMiddleware.php
@@ -2,10 +2,10 @@
 
 /**
  * @file
- * Contains \Drupal\Core\Test\EventSubscriber\TestHttpClientMiddleware.
+ * Contains \Drupal\Core\Test\HttpClientMiddleware\TestHttpClientMiddleware.
  */
 
-namespace Drupal\Core\Test\EventSubscriber;
+namespace Drupal\Core\Test\HttpClientMiddleware;
 
 use Psr\Http\Message\RequestInterface;
 
diff --git a/core/modules/simpletest/src/Tests/SimpleTestTest.php b/core/modules/simpletest/src/Tests/SimpleTestTest.php
index 540a838..1f97845 100644
--- a/core/modules/simpletest/src/Tests/SimpleTestTest.php
+++ b/core/modules/simpletest/src/Tests/SimpleTestTest.php
@@ -157,7 +157,7 @@ function stubTest() {
     // request. This allows the stub test to make requests. The event does not
     // fire here and drupal_generate_test_ua() can not generate a key for a
     // test in a test since the prefix has changed.
-    // @see \Drupal\Core\Test\EventSubscriber\TestHttpClientMiddleware::onBeforeSendRequest()
+    // @see \Drupal\Core\Test\HttpClientMiddleware\TestHttpClientMiddleware::onBeforeSendRequest()
     // @see drupal_generate_test_ua();
     $key_file = DRUPAL_ROOT . '/sites/simpletest/' . substr($this->databasePrefix, 10) . '/.htkey';
     $private_key = Crypt::randomBytesBase64(55);