[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 60974662b01e9fcf195a5b93bcbff316afe1fe4c..ef23ad7c39dd0bcf54b6e37f9834d6926dac6af6 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
@@ -293,4 +293,16 @@ 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();