More minor type improvements in dart:async.

sdk/lib/async/stream_impl.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 dart.async;
 
 /** Abstract and private interface for a place to put events. */
 abstract class _EventSink<T> {
   void _add(T data);
   void _addError(Object error, StackTrace stackTrace);
@@ skipping 325 matching lines @@
     assert(!_isCanceled);
     assert(!_isPaused);
     assert(!_inCallback);
     bool wasInputPaused = _isInputPaused;
 
     void sendError() {
       // If the subscription has been canceled while waiting for the cancel
       // future to finish we must not report the error.
       if (_isCanceled && !_waitsForCancel) return;
       _state |= _STATE_IN_CALLBACK;
+      // TODO(floitsch): this dynamic should be 'void'.
       if (_onError is ZoneBinaryCallback<dynamic, Object, StackTrace>) {
         ZoneBinaryCallback<dynamic, Object, StackTrace> errorCallback = _onError
             as Object/*=ZoneBinaryCallback<dynamic, Object, StackTrace>*/;
         _zone.runBinaryGuarded(errorCallback, error, stackTrace);
       } else {
-        _zone.runUnaryGuarded<dynamic, dynamic>(
-            _onError as Object/*=ZoneUnaryCallback<dynamic, dynamic>*/, error);
+        _zone.runUnaryGuarded<dynamic, Object>(
+            _onError as Object/*=ZoneUnaryCallback<dynamic, Object>*/, error);
       }
       _state &= ~_STATE_IN_CALLBACK;
     }
 
     if (_cancelOnError) {
       _state |= _STATE_WAIT_FOR_CANCEL;
       _cancel();
       if (_cancelFuture is Future &&
           !identical(_cancelFuture, Future._nullFuture)) {
         _cancelFuture.whenComplete(sendError);
@@ skipping 31 matching lines @@
     }
   }
 
   /**
    * Call a hook function.
    *
    * The call is properly wrapped in code to avoid other callbacks
    * during the call, and it checks for state changes after the call
    * that should cause further callbacks.
    */
-  void _guardCallback(callback) {
+  void _guardCallback(void callback()) {
     assert(!_inCallback);
     bool wasInputPaused = _isInputPaused;
     _state |= _STATE_IN_CALLBACK;
     callback();
     _state &= ~_STATE_IN_CALLBACK;
     _checkState(wasInputPaused);
   }
 
   /**
    * Check if the input needs to be informed of state changes.
@@ skipping 129 matching lines @@
   }
 }
 
 // Internal helpers.
 
 // Types of the different handlers on a stream. Types used to type fields.
 typedef void _DataHandler<T>(T value);
 typedef void _DoneHandler();
 
 /** Default data handler, does nothing. */
-void _nullDataHandler(var value) {}
+void _nullDataHandler(Object value) {}
 
 /** Default error handler, reports the error to the current zone's handler. */
-void _nullErrorHandler(error, [StackTrace stackTrace]) {
+void _nullErrorHandler(Object error, [StackTrace stackTrace]) {
   Zone.current.handleUncaughtError(error, stackTrace);
 }
 
 /** Default done handler, does nothing. */
 void _nullDoneHandler() {}
 
 /** A delayed event on a buffering stream subscription. */
 abstract class _DelayedEvent<T> {
   /** Added as a linked list on the [StreamController]. */
   _DelayedEvent next;
@@ skipping 472 matching lines @@
 
 /** An empty broadcast stream, sending a done event as soon as possible. */
 class _EmptyStream<T> extends Stream<T> {
   const _EmptyStream() : super._internal();
   bool get isBroadcast => true;
   StreamSubscription<T> listen(void onData(T data),
       {Function onError, void onDone(), bool cancelOnError}) {
     return new _DoneStreamSubscription<T>(onDone);
   }
 }