Issue #3296842: Move ResourceResponse to from rest module to Core-core

core/lib/Drupal/Core/ResourceResponse/ResourceResponse.php

+<?php
+
+namespace Drupal\Core\ResourceResponse;
+
+use Drupal\Core\Cache\CacheableResponseInterface;
+use Drupal\Core\Cache\CacheableResponseTrait;
+use Symfony\Component\HttpFoundation\Response;
+
+/**
+ * Contains data for serialization before sending the response.
+ *
+ * We do not want to abuse the $content property on the Response class to store
+ * our response data. $content implies that the provided data must either be a
+ * string or an object with a __toString() method, which is not a requirement
+ * for data used here.
+ *
+ * Routes that return this response must specify the '_format' requirement.
+ *
+ * @see \Drupal\Core\ResourceResponse\ModifiedResourceResponse
+ */
+class ResourceResponse extends Response implements CacheableResponseInterface, ResourceResponseInterface {
+
+  use CacheableResponseTrait;
+  use ResourceResponseTrait;
+
+  /**
+   * Constructor for ResourceResponse objects.
+   *
+   * @param mixed $data
+   *   Response data that should be serialized.
+   * @param int $status
+   *   The response status code.
+   * @param array $headers
+   *   An array of response headers.
+   */
+  public function __construct($data = NULL, $status = 200, $headers = []) {
+    $this->responseData = $data;
+    parent::__construct('', $status, $headers);
+  }
+
+}