Rename Date to DateTime.

tests/corelib/date_time7_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.
 
-// Test Date timeZoneName and timeZoneOffset getters.
+// Test DateTime timeZoneName and timeZoneOffset getters.
 
 testUtc() {
-  var d = new Date.fromString("2012-03-04T03:25:38.123Z");
+  var d = new DateTime.fromString("2012-03-04T03:25:38.123Z");
   Expect.equals("UTC", d.timeZoneName);
   Expect.equals(0, d.timeZoneOffset.inSeconds);
 }
 
 testLocal() {
   checkOffset(String name, Duration offset) {
     // Timezone abbreviations are not in bijection with their timezones.
     // For example AST stands for "Arab Standard Time" (UTC+03), as well as
     // "Arabian Standard Time" (UTC+04), or PST stands for Pacific Standard Time
     // and Philippine Standard Time.
     //
     // Hardcode some common timezones.
     if (name == "CET") {
       Expect.equals(1, offset.inHours);
     } else if (name == "CEST") {
       Expect.equals(2, offset.inHours);
     } else if (name == "GMT") {
       Expect.equals(0, offset.inSeconds);
     } else if (name == "EST") {
       Expect.equals(-5, offset.inHours);
     } else if (name == "EDT") {
       Expect.equals(-4, offset.inHours);
     } else if (name == "PDT") {
       Expect.equals(-7, offset.inHours);
     }
   }
 
-  var d = new Date.fromString("2012-01-02T13:45:23");
+  var d = new DateTime.fromString("2012-01-02T13:45:23");
   String name = d.timeZoneName;
   checkOffset(name, d.timeZoneOffset);
 
-  d = new Date.fromString("2012-07-02T13:45:23");
+  d = new DateTime.fromString("2012-07-02T13:45:23");
   name = d.timeZoneName;
   checkOffset(name, d.timeZoneOffset);
 }
 
 main() {
   testUtc();
   testLocal();
 }