Deprecate use of timezones.

tests/standalone/io/http_headers_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.
 
 #source("../../../runtime/bin/input_stream.dart");
 #source("../../../runtime/bin/output_stream.dart");
 #source("../../../runtime/bin/chunked_stream.dart");
 #source("../../../runtime/bin/string_stream.dart");
 #source("../../../runtime/bin/stream_util.dart");
 #source("../../../runtime/bin/http.dart");
@@ skipping 32 matching lines @@
   Expect.equals(1, headers[HttpHeaders.PRAGMA].length);
 
   headers.set(HttpHeaders.PRAGMA, ["pragma6", "pragma7"]);
   Expect.equals(2, headers[HttpHeaders.PRAGMA].length);
 
   headers.removeAll(HttpHeaders.PRAGMA);
   Expect.isNull(headers[HttpHeaders.PRAGMA]);
 }
 
 void testDate() {
-  Date date1 = new Date.withTimeZone(
-      1999, Date.JUN, 11, 18, 46, 53, 0, new TimeZone.utc());
+  Date date1 = new Date(1999, Date.JUN, 11, 18, 46, 53, 0, isUtc: true);
   String httpDate1 = "Fri, 11 Jun 1999 18:46:53 GMT";
-  Date date2 = new Date.withTimeZone(
-      2000, Date.AUG, 16, 12, 34, 56, 0, new TimeZone.utc());
+  Date date2 = new Date(2000, Date.AUG, 16, 12, 34, 56, 0, isUtc: true);
   String httpDate2 = "Wed, 16 Aug 2000 12:34:56 GMT";
 
   _HttpHeaders headers = new _HttpHeaders();
   Expect.isNull(headers.date);
   headers.date = date1;
   Expect.equals(date1, headers.date);
   Expect.equals(httpDate1, headers.value(HttpHeaders.DATE));
   Expect.equals(1, headers[HttpHeaders.DATE].length);
   headers.add(HttpHeaders.DATE, httpDate2);
   Expect.equals(1, headers[HttpHeaders.DATE].length);
   Expect.equals(date2, headers.date);
   Expect.equals(httpDate2, headers.value(HttpHeaders.DATE));
   headers.set(HttpHeaders.DATE, httpDate1);
   Expect.equals(1, headers[HttpHeaders.DATE].length);
   Expect.equals(date1, headers.date);
   Expect.equals(httpDate1, headers.value(HttpHeaders.DATE));
 
   headers.set(HttpHeaders.DATE, "xxx");
   Expect.equals("xxx", headers.value(HttpHeaders.DATE));
   Expect.equals(null, headers.date);
 }
 
 void testExpires() {
-  Date date1 = new Date.withTimeZone(
-      1999, Date.JUN, 11, 18, 46, 53, 0, new TimeZone.utc());
+  Date date1 = new Date(1999, Date.JUN, 11, 18, 46, 53, 0, isUtc: true);
   String httpDate1 = "Fri, 11 Jun 1999 18:46:53 GMT";
-  Date date2 = new Date.withTimeZone(
-      2000, Date.AUG, 16, 12, 34, 56, 0, new TimeZone.utc());
+  Date date2 = new Date(2000, Date.AUG, 16, 12, 34, 56, 0, isUtc: true);
   String httpDate2 = "Wed, 16 Aug 2000 12:34:56 GMT";
 
   _HttpHeaders headers = new _HttpHeaders();
   Expect.isNull(headers.expires);
   headers.expires = date1;
   Expect.equals(date1, headers.expires);
   Expect.equals(httpDate1, headers.value(HttpHeaders.EXPIRES));
   Expect.equals(1, headers[HttpHeaders.EXPIRES].length);
   headers.add(HttpHeaders.EXPIRES, httpDate2);
   Expect.equals(1, headers[HttpHeaders.EXPIRES].length);
@@ skipping 182 matching lines @@
 
 main() {
   testMultiValue();
   testExpires();
   testHost();
   testEnumeration();
   testHeaderValue();
   testContentType();
   testContentTypeCache();
 }