Update to Drupal 8.2.2. For more information, see https://www.drupal.org/project/drupal/releases/8.2.2

core/modules/taxonomy/tests/modules/vocabulary_serialization_test/src/VocabularyResponse.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Drupal\vocabulary_serialization_test;
+
+use Drupal\Core\Cache\CacheableResponse;
+use Drupal\taxonomy\VocabularyInterface;
+
+class VocabularyResponse extends CacheableResponse {
+
+  /**
+   * @var \Drupal\taxonomy\VocabularyInterface
+   */
+  protected $vocabulary;
+
+  public function setVocabulary(VocabularyInterface $vocabulary) {
+    $this->vocabulary = $vocabulary;
+  }
+
+}

core/modules/taxonomy/tests/modules/vocabulary_serialization_test/src/VocabularySerializationTestController.php

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+<?php
+
+namespace Drupal\vocabulary_serialization_test;
+
+use Drupal\taxonomy\VocabularyInterface;
+
+class VocabularySerializationTestController {
+
+  public function vocabularyResponse(VocabularyInterface $taxonomy_vocabulary) {
+    $response = new VocabularyResponse('this is the output');
+    $response->setVocabulary($taxonomy_vocabulary);
+    return $response;
+  }
+
+}

core/modules/taxonomy/tests/modules/vocabulary_serialization_test/vocabulary_serialization_test.info.yml

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+name: 'Vocabulary serialization test'
+type: module
+package: Testing
+version: VERSION
+core: 8.x
+dependencies:
+  - taxonomy

core/modules/taxonomy/tests/modules/vocabulary_serialization_test/vocabulary_serialization_test.routing.yml

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+vocabulary_serialization_test:
+  path: '/vocabulary_serialization_test/{taxonomy_vocabulary}'
+  defaults:
+    _controller: 'Drupal\vocabulary_serialization_test\VocabularySerializationTestController::vocabularyResponse'
+  requirements:
+    _access: 'TRUE'