Remove pseudo-shared Timer implementation.

tools/dom/src/native_DOMImplementation.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.
 
 part of html;
 
 class _Utils {
   static double dateTimeToDouble(DateTime dateTime) =>
       dateTime.millisecondsSinceEpoch.toDouble();
   static DateTime doubleToDateTime(double dateTime) {
@@ skipping 170 matching lines @@
     }
   });
 }
 
 final _printClosure = window.console.log;
 final _pureIsolatePrintClosure = (s) {
   _sendToHelperIsolate([_PRINT, s], null);
 };
 
 final _forwardingPrintClosure = _Utils.forwardingPrint;
+
+class _Timer implements Timer {
+  final canceller;
+
+  _Timer(this.canceller);
+
+  void cancel() { canceller(); }
+}
+
+get _timerFactoryClosure => (int milliSeconds, void callback(Timer timer), bool repeating) {

[vsm, 2013/04/04 13:41:49]

nit length

+  var maker;
+  var canceller;
+  if (repeating) {
+    maker = window._setInterval;
+    canceller = window._clearInterval;
+  } else {
+    maker = window._setTimeout;
+    canceller = window._clearTimeout;
+  }
+  Timer timer;
+  final int id = maker(() { callback(timer); }, milliSeconds);
+  timer = new _Timer(() { canceller(id); });
+  return timer;
+};
+
+class _PureIsolateTimer implements Timer {
+  final ReceivePort _port = new ReceivePort();
+  SendPort _sendPort; // Effectively final.
+
+  static SendPort _SEND_PORT;
+
+  _PureIsolateTimer(int milliSeconds, callback, repeating) {
+    _sendPort = _port.toSendPort();
+    _port.receive((msg, replyTo) {
+      assert(msg == _TIMER_PING);
+      callback(this);
+      if (!repeating) _cancel();
+    });
+
+    _send([_NEW_TIMER, milliSeconds, repeating]);
+  }
+
+  void cancel() {
+    _cancel();
+    _send([_CANCEL_TIMER]);
+  }
+
+  void _cancel() {
+    _port.close();
+  }
+
+  _send(msg) {
+    _sendToHelperIsolate(msg, _sendPort);
+  }
+}
+
+get _pureIsolateTimerFactoryClosure =>
+    ((int milliSeconds, void callback(Timer time), bool repeating) =>
+        new _PureIsolateTimer(milliSeconds, callback, repeating));