Use iterator, moveNext(), current.

pkg/http/lib/src/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.
 
 library utils;
 
 import 'dart:async';
 import 'dart:crypto';
 import 'dart:io';
 import 'dart:scalarlist';
@@ skipping 158 matching lines @@
 
 // TOOD(nweiz): Get rid of this once https://codereview.chromium.org/11293132/
 // is in.
 /// Runs [fn] for each element in [input] in order, moving to the next element
 /// only when the [Future] returned by [fn] completes. Returns a [Future] that
 /// completes when all elements have been processed.
 ///
 /// The return values of all [Future]s are discarded. Any errors will cause the
 /// iteration to stop and will be piped through the return value.
 Future forEachFuture(Iterable input, Future fn(element)) {
-  var iterator = input.iterator();
+  var iterator = input.iterator;
   Future nextElement(_) {
-    if (!iterator.hasNext) return new Future.immediate(null);
-    return fn(iterator.next()).chain(nextElement);
+    if (!iterator.moveNext()) return new Future.immediate(null);
+    return fn(iterator.current).chain(nextElement);
   }
   return nextElement(null);
 }
 
 /// Creates a temporary directory and passes its path to [fn]. Once the [Future]
 /// returned by [fn] completes, the temporary directory and all its contents
 /// will be deleted.
 Future withTempDir(Future fn(String path)) {
   var tempDir;
   var future = new Directory('').createTemp().chain((dir) {
     tempDir = dir;
     return fn(tempDir.path);
   });
   future.onComplete((_) => tempDir.delete(recursive: true));
   return future;
 }
 
 /// Configures [future] so that its result (success or exception) is passed on
 /// to [completer].
 void chainToCompleter(Future future, Completer completer) {
   future.handleException((e) {
     completer.completeException(e);
     return true;
   });
   future.then(completer.complete);
 }