Revert of Use ExclusiveStreamReader to lock Body.

LayoutTests/http/tests/fetch/script-tests/stream-reader.js

Index: LayoutTests/http/tests/fetch/script-tests/stream-reader.js
diff --git a/LayoutTests/http/tests/fetch/script-tests/stream-reader.js b/LayoutTests/http/tests/fetch/script-tests/stream-reader.js
index dc1b094a8030507326f9a497a773139515eceb6c..3a202716ac24c8779c5df5aca415bf5f26a7d152 100644
--- a/LayoutTests/http/tests/fetch/script-tests/stream-reader.js
+++ b/LayoutTests/http/tests/fetch/script-tests/stream-reader.js
@@ -88,28 +88,4 @@
       });
   }, 'read contents with ExclusiveStreamReader');
 
-promise_test(function(t) {
-    return fetch('/fetch/resources/progressive.php').then(function(res) {
-        assert_false(res.bodyUsed);
-        var reader = res.body.getReader();
-        assert_true(res.bodyUsed);
-        return res;
-      }).then(function(res) {
-        return res.text();
-      }).then(unreached_rejection(t), function() {
-        // text() should fail because bodyUsed is set.
-      });
-  }, 'acquiring a reader should set bodyUsed.');
-
-promise_test(function(t) {
-    return fetch('/fetch/resources/progressive.php').then(function(res) {
-        // We need to access body attribute to start the stream.
-        res.body;
-        assert_false(res.bodyUsed);
-        res.text();
-        assert_true(res.bodyUsed);
-        assert_throws({name: 'TypeError'}, function() { res.body.getReader() });
-      });
-  }, 'Setting bodyUsed means the body is locked.');
-
 done();