Make withLocale use a zone

test/number_closure_test.dart

 // 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.
 
 /**
  * Tests based on the closure number formatting tests.
  */
 library number_closure_test;
 
+import 'dart:async';
 import "package:intl/intl.dart";
 import "package:unittest/unittest.dart";
 
 main() {
   test("testVeryBigNumber", testVeryBigNumber);
   test("testStandardFormat", testStandardFormat);
   test("testNegativePercentage", testNegativePercentage);
   test("testCustomPercentage", testCustomPercentage);
   test("testBasicFormat", testBasicFormat);
   test("testGrouping", testGrouping);
   test("testPerMill", testPerMill);
   test("testQuotes", testQuotes);
   test("testZeros", testZeros);
   test("testExponential", testExponential);
   test("testPlusSignInExponentPart", testPlusSignInExponentPart);
   test("testApis", testApis);
   test("testLocaleSwitch", testLocaleSwitch);
+  test("testLocaleSwitchAsync", testLocaleSwitchAsync);
 }
 
 /**
  * Test two large numbers for equality, assuming that there may be some
  * loss of precision in the less significant digits.
  */
 veryBigNumberCompare(str1, str2) {
   return str1.length == str2.length &&
          str1.substring(0, 8) == str2.substring(0, 8);
 }
@@ skipping 338 matching lines @@
 
   fmt = new NumberFormat('#,###');
   str = fmt.format(1234567890);
   expect('1,234,567,890', str);
 }
 
 testLocaleSwitch() {
   Intl.withLocale("fr", verifyFrenchLocale);
 }
 
+testLocaleSwitchAsync() {
+  Intl.withLocale("fr", () {
+    new Timer(new Duration(milliseconds:10), expectAsync(verifyFrenchLocale));
+  });
+  // Verify that things running outside the zone still get en_US.
+  testStandardFormat();
+}
+
 void verifyFrenchLocale() {
   var fmt = new NumberFormat('#,###');
   var str = fmt.format(1234567890);
-  expect('1\u00a0234\u00a0567\u00a0890', str);
+  expect(str, '1\u00a0234\u00a0567\u00a0890');
 }