Make verifiedLocale work differently depending on what it's verifying for

pkg/intl/example/basic/basic_example.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.
 
 /**
  * This provides a basic example of internationalization usage. It uses the
  * local variant of all the facilities, meaning that libraries with the
  * data for all the locales are directly imported by the program. More realistic
  * examples might read the data from files or over the web, which uses the
  * same APIs but requires different imports.
@@ skipping 38 matching lines @@
   var de = new Intl('de_DE');
   var th = new Intl('th_TH');
   // This defines a message that can be internationalized. It is written as a
   // function that returns the result of an Intl.message call. The primary
   // parameter is a string that may use interpolation.
   runAt(time, date) =>
       Intl.message('Ran at $time on $date', name: 'runAt', args: [time, date]);
   printForLocale(aDate, new Intl(), runAt);
   printForLocale(aDate, de, runAt);
   printForLocale(aDate, th, runAt);
+  // Example making use of the return value from withLocale;
+  var useReturnValue = Intl.withLocale(th.locale, () => runAt('now', 'today'));
+  doThisWithTheOutput(useReturnValue);
 }
 
 printForLocale(aDate, intl, operation) {
   var hmsFormat = intl.date().add_Hms();
   var dayFormat = intl.date().add_yMMMMEEEEd();
   var time = hmsFormat.format(aDate);
   var day = dayFormat.format(aDate);
   Intl.withLocale(intl.locale, () { doThisWithTheOutput(operation(time,day));});
 }