Update WritableStream to new standard version

third_party/WebKit/LayoutTests/http/tests/streams/writable-streams/start.js

-'use strict';
-
-if (self.importScripts) {
-  self.importScripts('/resources/testharness.js');
-  self.importScripts('../resources/test-utils.js');
-  self.importScripts('../resources/recording-streams.js');
-}
-
-promise_test(() => {
-  let resolveStartPromise;
-  const ws = recordingWritableStream({
-    start() {
-      return new Promise(resolve => {
-        resolveStartPromise = resolve;
-      });
-    }
-  });
-
-  const writer = ws.getWriter();
-
-  assert_equals(writer.desiredSize, 1, 'desiredSize should be 1');
-  writer.write('a');
-  assert_equals(writer.desiredSize, 0, 'desiredSize should be 0 after writer.write()');
-
-  // Wait and verify that write isn't called.
-  return flushAsyncEvents()
-      .then(() => {
-        assert_array_equals(ws.events, [], 'write should not be called until start promise resolves');
-        resolveStartPromise();
-        return writer.ready;
-      })
-      .then(() => assert_array_equals(ws.events, ['write', 'a'],
-                                      'write should not be called until start promise resolves'));
-}, 'underlying sink\'s write should not be called until start finishes');
-
-promise_test(() => {
-  let resolveStartPromise;
-  const ws = recordingWritableStream({
-    start() {
-      return new Promise(resolve => {
-        resolveStartPromise = resolve;
-      });
-    }
-  });
-
-  const writer = ws.getWriter();
-
-  writer.close();
-  assert_equals(writer.desiredSize, 1, 'desiredSize should be 1');
-
-  // Wait and verify that write isn't called.
-  return flushAsyncEvents().then(() => {
-    assert_array_equals(ws.events, [], 'close should not be called until start promise resolves');
-    resolveStartPromise();
-    return writer.closed;
-  });
-}, 'underlying sink\'s close should not be called until start finishes');
-
-test(() => {
-  const passedError = new Error('horrible things');
-
-  let writeCalled = false;
-  let closeCalled = false;
-  assert_throws(passedError, () => {
-    // recordingWritableStream cannot be used here because the exception in the
-    // constructor prevents assigning the object to a variable.
-    new WritableStream({
-      start() {
-        throw passedError;
-      },
-      write() {
-        writeCalled = true;
-      },
-      close() {
-        closeCalled = true;
-      }
-    });
-  }, 'constructor should throw passedError');
-  assert_false(writeCalled, 'write should not be called');
-  assert_false(closeCalled, 'close should not be called');
-}, 'underlying sink\'s write or close should not be called if start throws');
-
-promise_test(() => {
-  const ws = recordingWritableStream({
-    start() {
-      return Promise.reject();
-    }
-  });
-
-  // Wait and verify that write or close aren't called.
-  return flushAsyncEvents()
-      .then(() => assert_array_equals(ws.events, [], 'write and close should not be called'));
-}, 'underlying sink\'s write or close should not be invoked if the promise returned by start is rejected');
-
-promise_test(t => {
-  const rejection = { name: 'this is checked' };
-  const ws = new WritableStream({
-    start() {
-      return {
-        then(onFulfilled, onRejected) { onRejected(rejection); }
-      };
-    }
-  });
-  return promise_rejects(t, rejection, ws.getWriter().closed, 'closed promise should be rejected');
-}, 'returning a thenable from start() should work');
-
-done();