Big merge from experimental to bleeding edge.

pkg/oauth2/lib/src/credentials.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 credentials;
 
-import 'dart:json';
+import 'dart:async';
+import 'dart:json' as JSON;
 import 'dart:uri';
 
 import '../../../http/lib/http.dart' as http;
 import 'handle_access_token_response.dart';
 import 'utils.dart';
 
 /// Credentials that prove that a client is allowed to access a resource on the
 /// resource owner's behalf. These credentials are long-lasting and can be
 /// safely persisted across multiple runs of the program.
 ///
@@ skipping 127 matching lines @@
       String identifier,
       String secret,
       {List<String> newScopes,
        http.Client httpClient}) {
     var scopes = this.scopes;
     if (newScopes != null) scopes = newScopes;
     if (scopes == null) scopes = <String>[];
     if (httpClient == null) httpClient = new http.Client();
 
     var startTime = new Date.now();
-    return async.chain((_) {
+    return async.then((_) {
       if (refreshToken == null) {
         throw new StateError("Can't refresh credentials without a refresh "
             "token.");
       } else if (tokenEndpoint == null) {
         throw new StateError("Can't refresh credentials without a token "
             "endpoint.");
       }
 
       var fields = {
         "grant_type": "refresh_token",
         "refresh_token": refreshToken,
         // TODO(nweiz): the spec recommends that HTTP basic auth be used in
         // preference to form parameters, but Google doesn't support that.
         // Should it be configurable?
         "client_id": identifier,
         "client_secret": secret
       };
       if (!scopes.isEmpty) fields["scope"] = Strings.join(scopes, ' ');
 
       return httpClient.post(tokenEndpoint, fields: fields);
-    }).transform((response) {
+    }).then((response) {
       return handleAccessTokenResponse(
           response, tokenEndpoint, startTime, scopes);
-    }).transform((credentials) {
+    }).then((credentials) {
       // The authorization server may issue a new refresh token. If it doesn't,
       // we should re-use the one we already have.
       if (credentials.refreshToken != null) return credentials;
       return new Credentials(
           credentials.accessToken,
           this.refreshToken,
           credentials.tokenEndpoint,
           credentials.scopes,
           credentials.expiration);
     });
   }
 }