Fix chainToCompleter.

utils/pub/utils.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /// Generic utility functions. Stuff that should possibly be in core.
 library utils;
 
 import 'dart:async';
 import 'dart:crypto';
 import 'dart:isolate';
@@ skipping 102 matching lines @@
 /// Returns a [Future] that completes in [milliseconds].
 Future sleep(int milliseconds) {
   var completer = new Completer();
   new Timer(milliseconds, (_) => completer.complete());
   return completer.future;
 }
 
 /// Configures [future] so that its result (success or exception) is passed on
 /// to [completer].
 void chainToCompleter(Future future, Completer completer) {
-  future
-    .then(completer.complete)
-    .catchError((e) {
-      completer.completeError(e.error, e.stackTrace);
-    });
+  future.then((value) => completer.complete(value),
+      onError: (e) => completer.completeError(e.error, e.stackTrace));
 }
 
 // TODO(nweiz): unify the following functions with the utility functions in
 // pkg/http.
 
 /// Like [String.split], but only splits on the first occurrence of the pattern.
 /// This will always return an array of two elements or fewer.
 List<String> split1(String toSplit, String pattern) {
   if (toSplit.isEmpty) return <String>[];
 
@@ skipping 52 matching lines @@
 // TODO(rnystrom): Remove this when #7781 is fixed.
 /// When an error is rethrown in an async callback, you can end up with nested
 /// AsyncErrors. This unwraps them to find the real originating error.
 getRealError(error) {
   while (error is AsyncError) {
     error = error.error;
   }
 
   return error;
 }