[Fetch API] Reflect spec changes of bodyUsed property

third_party/WebKit/LayoutTests/http/tests/fetch/script-tests/fetch.js

Index: third_party/WebKit/LayoutTests/http/tests/fetch/script-tests/fetch.js
diff --git a/third_party/WebKit/LayoutTests/http/tests/fetch/script-tests/fetch.js b/third_party/WebKit/LayoutTests/http/tests/fetch/script-tests/fetch.js
index eb97820cd9333628a1d78bba5ec7ea18c694151b..d2d188c6acc72789ad215df24bf776f2f9ecc66a 100644
--- a/third_party/WebKit/LayoutTests/http/tests/fetch/script-tests/fetch.js
+++ b/third_party/WebKit/LayoutTests/http/tests/fetch/script-tests/fetch.js
@@ -356,4 +356,16 @@ test(function(t) {
   'Destroying the execution context while fetch is happening should not ' +
   'cause a crash.');
 
+test(t => {
+    var req = new Request('/', {method: 'POST', body: ''});
+    fetch(req);
+    assert_true(req.bodyUsed);
+}, 'Calling fetch() disturbs body if not null');
+
+test(t => {
+    var req = new Request('/', {method: 'POST'});
+    fetch(req);
+    assert_false(req.bodyUsed);
+}, 'Calling fetch() doesn\'t disturb body if null');
+
 done();