Fix Windows time zone name extraction. Update API docs

tests/corelib/date_time_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.
 
 import "package:expect/expect.dart";
 
 // Dart test program for DateTime.
 
 bool get supportsMicroseconds =>
     new DateTime.fromMicrosecondsSinceEpoch(1).microsecondsSinceEpoch == 1;
@@ skipping 1216 matching lines @@
   d = new DateTime(2011, 9, 30, 23, 45, 37, 0);
   Expect.equals(DateTime.FRIDAY, d.weekday);
 }
 
 void testToStrings() {
   void test(date, time) {
     { // UTC time.
       String source1 = "$date ${time}Z";
       String source2 = "${date}T${time}Z";
       var utcTime1 = DateTime.parse(source1);
-      var utcTime2 = DateTime.parse(source1);
+      var utcTime2 = DateTime.parse(source2);
       Expect.isTrue(utcTime1.isUtc);
       Expect.equals(utcTime1, utcTime2);
       Expect.equals(source1, utcTime1.toString());
       Expect.equals(source2, utcTime1.toIso8601String());
     }
     {  // Local time
       String source1 = "$date $time";
       String source2 = "${date}T$time";
       var utcTime1 = DateTime.parse(source1);
-      var utcTime2 = DateTime.parse(source1);
+      var utcTime2 = DateTime.parse(source2);
       Expect.isFalse(utcTime1.isUtc);
       Expect.equals(utcTime1, utcTime2);
       Expect.equals(source1, utcTime1.toString());
       Expect.equals(source2, utcTime1.toIso8601String());
     }
   }
   test("2000-01-01", "12:00:00.000");
   test("-2000-01-01", "12:00:00.000");
   test("1970-01-01", "00:00:00.000");
   test("1969-12-31", "23:59:59.999");
@@ skipping 77 matching lines @@
   testSubAdd();
   testUnderflowAndOverflow();
   testDateStrings();
   testEquivalentYears();
   testExtremes();
   testFarAwayDates();
   testWeekday();
   testToStrings();
   testIsoString();
 }