Revert some changes

src/Controller/Component/RequestHandlerComponent.php

@@ -287,7 +287,7 @@ class RequestHandlerComponent extends Component
         }
         /** @var \Cake\Controller\Controller $controller */
         $controller = $event->getSubject();
-        $response = $response->withStringBody($controller->requestAction($url, [
+        $response->body($controller->requestAction($url, [
             'return',
             'bare' => false,
             'environment' => [

src/Http/Response.php

@@ -624,8 +624,7 @@ class Response implements ResponseInterface
         );
 
         if (in_array($this->_status, [304, 204])) {
-            $this->_createStream();
-            $this->stream->write('');
+            $this->body('');
         }
     }
 

src/Http/ResponseTransformer.php

@@ -251,7 +251,7 @@ class ResponseTransformer
     protected static function getStream($response)
     {
         $stream = 'php://memory';
-        $body = $response->getBody();
+        $body = $response->body();
         if (is_string($body) && strlen($body)) {
             $stream = new Stream('php://memory', 'wb');
             $stream->write($body);

src/Routing/Dispatcher.php

@@ -65,7 +65,7 @@ class Dispatcher
         $actionDispatcher = new ActionDispatcher(null, $this->getEventManager(), $this->_filters);
         $response = $actionDispatcher->dispatch($request, $response);
         if ($request->getParam('return', null) !== null) {
-            return $response->getBody();
+            return $response->body();
         }
 
         return $response->send();