[Fetch API] |(new Response(stream)).body| should return |stream|

third_party/WebKit/LayoutTests/http/tests/fetch/script-tests/response-stream-construction.js

 // This file contains tests for Response construction with a readable stream.
 // Move these tests to response.js once the feature gets stable.
 
 if (self.importScripts) {
   importScripts('../resources/fetch-test-helpers.js');
   importScripts('/streams/resources/rs-utils.js');
 }
 
 test(() => {
     var controller;
     var stream = new ReadableStream({start: c => controller = c});
 
     var response = new Response(stream);
-    // TODO(yhirano): This should be assert_equals.
-    assert_not_equals(response.body, stream);
+    assert_equals(response.body, stream);
   }, 'Response constructed with a stream');
 
 promise_test(() => {
     var controller;
     var stream = new ReadableStream({start: c => controller = c});
     controller.enqueue(new Uint8Array([0x68, 0x65, 0x6c, 0x6c, 0x6f]));
     controller.enqueue(new Uint8Array([0x77, 0x6f, 0x72, 0x6c, 0x64]));
     controller.close();
     assert_false(stream.locked);
     var response = new Response(stream);
@@ skipping 61 matching lines @@
 
 promise_test(t => {
     var controller;
     var stream = new ReadableStream({start: c => controller = c});
     setTimeout(() => controller.enqueue('hello'), 1);
     var response = new Response(stream);
     return promise_rejects(t, TypeError(), response.text());
   }, 'Response constructed stream with a string chunk');
 
 done();