Typecheck constructor initializers properly

test/dart_codegen/expect/async/stream_transformers.dart

 part of dart.async;
  class _EventSinkWrapper<T> implements EventSink<T> {_EventSink _sink;
  _EventSinkWrapper(this._sink);
  void add(T data) {
   _sink._add(data);
   }
  void addError(error, [StackTrace stackTrace]) {
   _sink._addError(error, stackTrace);
   }
  void close() {
@@ skipping 77 matching lines @@
  Stream<T> bind(Stream<S> stream) => new _BoundSinkStream<S, T>(stream, _sinkMapper);
 }
  class _BoundSinkStream<S, T> extends Stream<T> {final _SinkMapper<S, T> _sinkMapper;
  final Stream<S> _stream;
  bool get isBroadcast => _stream.isBroadcast;
  _BoundSinkStream(this._stream, this._sinkMapper);
  StreamSubscription<T> listen(void onData(T event), {
 Function onError, void onDone(), bool cancelOnError}
 ) {
 cancelOnError = identical(true, cancelOnError);
- StreamSubscription<T> subscription = ((__x118) => DDC$RT.cast(__x118, DDC$RT.type((_SinkTransformerStreamSubscription<dynamic, dynamic> _) {
+ StreamSubscription<T> subscription = ((__x123) => DDC$RT.cast(__x123, DDC$RT.type((_SinkTransformerStreamSubscription<dynamic, dynamic> _) {
 }
 ), DDC$RT.type((StreamSubscription<T> _) {
 }
-), "CastExact", """line 186, column 42 of dart:async/stream_transformers.dart: """, __x118 is StreamSubscription<T>, false))(new _SinkTransformerStreamSubscription(_stream, _sinkMapper, onData, onError, onDone, cancelOnError));
+), "CastExact", """line 186, column 42 of dart:async/stream_transformers.dart: """, __x123 is StreamSubscription<T>, false))(new _SinkTransformerStreamSubscription(_stream, _sinkMapper, onData, onError, onDone, cancelOnError));
  return subscription;
 }
 }
  typedef void _TransformDataHandler<S, T>(S data, EventSink<T> sink);
  typedef void _TransformErrorHandler<T>(Object error, StackTrace stackTrace, EventSink<T> sink);
  typedef void _TransformDoneHandler<T>(EventSink<T> sink);
  class _HandlerEventSink<S, T> implements EventSink<S> {final _TransformDataHandler<S, T> _handleData;
  final _TransformErrorHandler<T> _handleError;
  final _TransformDoneHandler<T> _handleDone;
  final EventSink<T> _sink;
  _HandlerEventSink(this._handleData, this._handleError, this._handleDone, this._sink);
  void add(S data) => _handleData(data, _sink);
  void addError(Object error, [StackTrace stackTrace]) => _handleError(error, stackTrace, _sink);
  void close() => _handleDone(_sink);
 }
  class _StreamHandlerTransformer<S, T> extends _StreamSinkTransformer<S, T> {_StreamHandlerTransformer({
 void handleData(S data, EventSink<T> sink), void handleError(Object error, StackTrace stackTrace, EventSink<T> sink), void handleDone(EventSink<T> sink)}
-) : super(((__x125) => DDC$RT.wrap((dynamic f(EventSink<T> __u120)) {
-dynamic c(EventSink<T> x0) => ((__x119) => DDC$RT.cast(__x119, dynamic, DDC$RT.type((EventSink<S> _) {
+) : super(((__x130) => DDC$RT.wrap((dynamic f(EventSink<T> __u125)) {
+dynamic c(EventSink<T> x0) => ((__x124) => DDC$RT.cast(__x124, dynamic, DDC$RT.type((EventSink<S> _) {
 }
-), "CastResult", """line 233, column 15 of dart:async/stream_transformers.dart: """, __x119 is EventSink<S>, false))(f(x0));
+), "CastResult", """line 233, column 15 of dart:async/stream_transformers.dart: """, __x124 is EventSink<S>, false))(f(x0));
  return f == null ? null : c;
 }
-, __x125, DDC$RT.type((__t123<T> _) {
+, __x130, DDC$RT.type((__t128<T> _) {
 }
-), DDC$RT.type((__t121<T, S> _) {
+), DDC$RT.type((__t126<T, S> _) {
 }
-), "WrapLiteral", """line 233, column 15 of dart:async/stream_transformers.dart: """, __x125 is __t121<T, S>))((EventSink<T> outputSink) {
+), "WrapLiteral", """line 233, column 15 of dart:async/stream_transformers.dart: """, __x130 is __t126<T, S>))((EventSink<T> outputSink) {
 if (handleData == null) handleData = _defaultHandleData;
  if (handleError == null) handleError = _defaultHandleError;
  if (handleDone == null) handleDone = _defaultHandleDone;
  return new _HandlerEventSink<S, T>(handleData, handleError, handleDone, outputSink);
 }
 ));
  Stream<T> bind(Stream<S> stream) {
 return super.bind(stream);
 }
  static void _defaultHandleData(var data, EventSink sink) {
@@ skipping 18 matching lines @@
 Function onError, void onDone(), bool cancelOnError}
 ) {
 cancelOnError = identical(true, cancelOnError);
  StreamSubscription<T> result = _transformer(_stream, cancelOnError);
  result.onData(onData);
  result.onError(onError);
  result.onDone(onDone);
  return result;
 }
 }
- typedef EventSink<S> __t121<T, S>(EventSink<T> __u122);
- typedef dynamic __t123<T>(EventSink<T> __u124);
+ typedef EventSink<S> __t126<T, S>(EventSink<T> __u127);
+ typedef dynamic __t128<T>(EventSink<T> __u129);