Refactor Future constructors.

tests/compiler/dart2js/analyze_only_test.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.
 
 // Smoke test of the dart2js compiler API.
 library analyze_only;
 
 import "package:expect/expect.dart";
 import 'dart:async';
 import 'dart:uri';
 
 import '../../utils/dummy_compiler_test.dart' as dummy;
 import '../../../sdk/lib/_internal/compiler/compiler.dart';
 
 runCompiler(String main, List<String> options,
             onValue(String code, List errors, List warnings)) {
   List errors = new List();
   List warnings = new List();
 
   Future<String> localProvider(Uri uri) {
     if (uri.scheme != 'main') return dummy.provider(uri);
-    return new Future<String>.immediate(main);
+    return new Future<String>.value(main);
   }
 
   void localHandler(Uri uri, int begin, int end,
                     String message, Diagnostic kind) {
     dummy.handler(uri, begin, end, message, kind);
     if (kind == Diagnostic.ERROR) {
       errors.add(message);
     } else if (kind == Diagnostic.WARNING) {
       warnings.add(message);
     }
@@ skipping 118 matching lines @@
   // --analyze-signatures-only implies --analyze-only
   runCompiler(
     "",
     ['--analyze-signatures-only', '--analyze-all'],
     (String code, List errors, List warnings) {
       Expect.isNull(code);
       Expect.isTrue(errors.isEmpty);
       Expect.isTrue(warnings.isEmpty);
     });
 }