Update WritableStream to new standard version

third_party/WebKit/Source/core/streams/ReadableStream.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 (function(global, binding, v8) {
   'use strict';
 
   const _reader = v8.createPrivateSymbol('[[reader]]');
   const _storedError = v8.createPrivateSymbol('[[storedError]]');
   const _controller = v8.createPrivateSymbol('[[controller]]');
@@ skipping 251 matching lines @@
       return true;
     }
 
     function pump() {
       if (shuttingDown) {
         return;
       }
       const desiredSize =
           binding.WritableStreamDefaultWriterGetDesiredSize(writer);
       if (desiredSize === null) {
-        writableError(binding.getWritableStreamStoredError(dest));
+        // This can happen if abort() is queued but not yet started when
+        // pipeTo() is called. In that case [[storedError]] is not set yet, and
+        // we need to wait until it is before we can cancel the pipe. Once
+        // [[storedError]] has been set, the rejection handler set on the writer
+        // closed promise above will detect it, so all we need to do here is
+        // nothing.
+        return;
       }
       if (desiredSize <= 0) {
         thenPromise(
             binding.getWritableStreamDefaultWriterReadyPromise(writer), pump,
             writableError);
         return;
       }
       reading = true;
       // TODO(ricea): Delay reads heuristically when desiredSize is low.
       thenPromise(
@@ skipping 824 matching lines @@
       (underlyingSource, strategy) => {
         return new ReadableStream(
             underlyingSource, strategy, createWithExternalControllerSentinel);
       };
 
   // Temporary exports while pipeTo() and pipeThrough() are behind flags
   binding.ReadableStream_prototype_pipeThrough =
       ReadableStream_prototype_pipeThrough;
   binding.ReadableStream_prototype_pipeTo = ReadableStream_prototype_pipeTo;
 });