pkg/dev_compiler/tool/input_sdk/lib/html/dart2js/html_dart2js.dart

Index: pkg/dev_compiler/tool/input_sdk/lib/html/dart2js/html_dart2js.dart
diff --git a/pkg/dev_compiler/tool/input_sdk/lib/html/dart2js/html_dart2js.dart b/pkg/dev_compiler/tool/input_sdk/lib/html/dart2js/html_dart2js.dart
index 9798bbefa4c43d904715c25d1b97cfc428d4dff0..670e03945ee2c317dcdf21f19296812bf8335699 100644
--- a/pkg/dev_compiler/tool/input_sdk/lib/html/dart2js/html_dart2js.dart
+++ b/pkg/dev_compiler/tool/input_sdk/lib/html/dart2js/html_dart2js.dart
@@ -36568,7 +36568,9 @@ class _BeforeUnloadEventStreamProvider implements
   const _BeforeUnloadEventStreamProvider(this._eventType);
 
   Stream<BeforeUnloadEvent> forTarget(EventTarget e, {bool useCapture: false}) {
-    var stream = new _EventStream(e, _eventType, useCapture);
+    // Specify the generic type for EventStream only in dart2js to avoid
+    // checked mode errors in dartium.
+    var stream = new _EventStream<BeforeUnloadEvent>(e, _eventType, useCapture);
     var controller = new StreamController<BeforeUnloadEvent>(sync: true);
 
     stream.listen((event) {
@@ -36584,12 +36586,16 @@ class _BeforeUnloadEventStreamProvider implements
   }
 
   ElementStream<BeforeUnloadEvent> forElement(Element e, {bool useCapture: false}) {
-    return new _ElementEventStreamImpl(e, _eventType, useCapture);
+    // Specify the generic type for _ElementEventStreamImpl only in dart2js to
+    // avoid checked mode errors in dartium.
+    return new _ElementEventStreamImpl<BeforeUnloadEvent>(e, _eventType, useCapture);
   }
 
   ElementStream<BeforeUnloadEvent> _forElementList(ElementList e,
       {bool useCapture: false}) {
-    return new _ElementListEventStreamImpl(e, _eventType, useCapture);
+    // Specify the generic type for _ElementEventStreamImpl only in dart2js to
+    // avoid checked mode errors in dartium.
+    return new _ElementListEventStreamImpl<BeforeUnloadEvent>(e, _eventType, useCapture);
   }
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
@@ -39931,7 +39937,7 @@ class EventStreamProvider<T extends Event> {
    * [addEventListener](http://docs.webplatform.org/wiki/dom/methods/addEventListener)
    */
   ElementStream<T> _forElementList(ElementList e, {bool useCapture: false}) {
-    return new _ElementListEventStreamImpl(e, _eventType, useCapture);
+    return new _ElementListEventStreamImpl<T>(e, _eventType, useCapture);
   }
 
   /**
@@ -40081,13 +40087,21 @@ class _EventStreamSubscription<T extends Event> extends StreamSubscription<T> {
   EventListener _onData;
   final bool _useCapture;
 
-  // TODO(jacobr): for full strong mode correctness we should write
-  // _onData = onData == null ? null : _wrapZone/*<Event, dynamic>*/((e) => onData(e as T))
-  // but that breaks 114 co19 tests as well as multiple html tests as it is reasonable
-  // to pass the wrong type of event object to an event listener as part of a
-  // test.
+  // TODO(leafp): It would be better to write this as
+  // _onData = onData == null ? null :
+  //   onData is _wrapZoneCallback<Event, dynamic>
+  //     ? _wrapZone/*<Event, dynamic>*/(onData)
+  //     : _wrapZone/*<Event, dynamic>*/((e) => onData(e as T))
+  // In order to support existing tests which pass the wrong type of events but
+  // use a more general listener, without causing as much slowdown for things
+  // which are typed correctly.  But this currently runs afoul of restrictions
+  // on is checks for compatibility with the VM.
   _EventStreamSubscription(this._target, this._eventType, void onData(T event),
-      this._useCapture) : _onData = _wrapZone/*<Event, dynamic>*/(onData) {
+                           this._useCapture) :
+      _onData = onData == null
+      ? null
+      : _wrapZone/*<Event, dynamic>*/((e) => (onData as dynamic)(e))
+  {
     _tryResume();
   }
 
@@ -40149,9 +40163,9 @@ class _EventStreamSubscription<T extends Event> extends StreamSubscription<T> {
     }
   }
 
-  Future asFuture([var futureValue]) {
+  Future/*<E>*/ asFuture/*<E>*/([var/*=E*/ futureValue]) {
     // We just need a future that will never succeed or fail.
-    Completer completer = new Completer();
+    var completer = new Completer/*<E>*/();
     return completer.future;
   }
 }
@@ -42527,7 +42541,7 @@ class _WrappedList<E extends Node> extends ListBase<E>
 
   // Iterable APIs
 
-  Iterator<E> get iterator => new _WrappedIterator(_list.iterator);
+  Iterator<E> get iterator => new _WrappedIterator<E>(_list.iterator);
 
   int get length => _list.length;
 
@@ -43387,17 +43401,13 @@ _wrapZoneCallback/*<A, R>*/ _wrapZone/*<A, R>*/(_wrapZoneCallback/*<A, R>*/ call
   // For performance reasons avoid wrapping if we are in the root zone.
   if (Zone.current == Zone.ROOT) return callback;
   if (callback == null) return null;
-  // TODO(jacobr): we cast to _wrapZoneCallback/*<A, R>*/ to hack around missing
-  // generic method support in zones.
-  return Zone.current.bindUnaryCallback(callback, runGuarded: true) as _wrapZoneCallback/*<A, R>*/;
+  return Zone.current.bindUnaryCallback/*<R, A>*/(callback, runGuarded: true);
 }
 
 _wrapZoneBinaryCallback/*<A, B, R>*/ _wrapBinaryZone/*<A, B, R>*/(_wrapZoneBinaryCallback/*<A, B, R>*/ callback) {
   if (Zone.current == Zone.ROOT) return callback;
   if (callback == null) return null;
-  // We cast to _wrapZoneBinaryCallback/*<A, B, R>*/ to hack around missing
-  // generic method support in zones.
-  return Zone.current.bindBinaryCallback(callback, runGuarded: true) as _wrapZoneBinaryCallback/*<A, B, R>*/;
+  return Zone.current.bindBinaryCallback/*<R, A, B>*/(callback, runGuarded: true);
 }
 
 /**