Make new StreamController be async by default.

sdk/lib/html/dart2js/html_dart2js.dart

Index: sdk/lib/html/dart2js/html_dart2js.dart
diff --git a/sdk/lib/html/dart2js/html_dart2js.dart b/sdk/lib/html/dart2js/html_dart2js.dart
index 021a3ca53e198019a839085e18344c8c674afc6c..3c3799c99164f12b00a14e671c1b3c0604d5c239 100644
--- a/sdk/lib/html/dart2js/html_dart2js.dart
+++ b/sdk/lib/html/dart2js/html_dart2js.dart
@@ -5961,14 +5961,14 @@ class DialogElement extends Element native "HTMLDialogElement" {
 // http://www.w3.org/TR/file-system-api/#the-directoryentry-interface
 @Experimental
 class DirectoryEntry extends Entry native "DirectoryEntry" {
-  
+
   /**
    * Create a new directory with the specified `path`. If `exclusive` is true,
    * the returned Future will complete with an error if a directory already
    * exists with the specified `path`.
    */
   Future<Entry> createDirectory(String path, {bool exclusive: false}) {
-    return _getDirectory(path, options: 
+    return _getDirectory(path, options:
         {'create': true, 'exclusive': exclusive});
   }
 
@@ -5989,7 +5989,7 @@ class DirectoryEntry extends Entry native "DirectoryEntry" {
   Future<Entry> createFile(String path, {bool exclusive: false}) {
     return _getFile(path, options: {'create': true, 'exclusive': exclusive});
   }
-  
+
   /**
    * Retrieve an already existing file entry. The returned future will
    * result in an error if a file at `path` does not exist or if the item at
@@ -10630,7 +10630,7 @@ class Geolocation native "Geolocation" {
 
     int watchId;
     var controller;
-    controller = new StreamController<Geoposition>(
+    controller = new StreamController<Geoposition>(sync: true,
       onListen: () {
         assert(watchId == null);
         watchId = $dom_watchPosition(
@@ -15384,18 +15384,18 @@ class Navigator native "Navigator" {
    *       document.body.append(video);
    *     });
    *
-   * The user can also pass in Maps to the audio or video parameters to specify 
-   * mandatory and optional constraints for the media stream. Not passing in a 
-   * map, but passing in `true` will provide a MediaStream with audio or 
+   * The user can also pass in Maps to the audio or video parameters to specify
+   * mandatory and optional constraints for the media stream. Not passing in a
+   * map, but passing in `true` will provide a MediaStream with audio or
    * video capabilities, but without any additional constraints. The particular
-   * constraint names for audio and video are still in flux, but as of this 
+   * constraint names for audio and video are still in flux, but as of this
    * writing, here is an example providing more constraints.
    *
    *     window.navigator.getUserMedia(
-   *         audio: true, 
-   *         video: {'mandatory': 
+   *         audio: true,
+   *         video: {'mandatory':
    *                    { 'minAspectRatio': 1.333, 'maxAspectRatio': 1.334 },
-   *                 'optional': 
+   *                 'optional':
    *                    [{ 'minFrameRate': 60 },
    *                     { 'maxWidth': 640 }]
    *     });
@@ -16242,7 +16242,7 @@ class Notation extends Node native "Notation" {
 @Experimental // experimental
 class Notification extends EventTarget native "Notification" {
 
-  factory Notification(String title, {String titleDir: null, String body: null, 
+  factory Notification(String title, {String titleDir: null, String body: null,
       String bodyDir: null, String tag: null, String iconUrl: null}) {
 
     var parsedOptions = {};
@@ -17870,7 +17870,7 @@ class RtcIceCandidate native "RTCIceCandidate,mozRTCIceCandidate" {
     // the unprefixed RTCIceCandidate in Firefox (currently both are defined,
     // but one can't be used as a constructor).
     var constructorName = JS('', 'window[#]',
-        Device.isFirefox ? '${Device.propertyPrefix}RTCIceCandidate' : 
+        Device.isFirefox ? '${Device.propertyPrefix}RTCIceCandidate' :
         'RTCIceCandidate');
     return JS('RtcIceCandidate', 'new #(#)', constructorName,
         convertDartToNative_SerializedScriptValue(dictionary));
@@ -17935,7 +17935,7 @@ class RtcPeerConnection extends EventTarget native "RTCPeerConnection,mozRTCPeer
     // Currently in Firefox some of the RTC elements are defined but throw an
     // error unless the user has specifically enabled them in their
     // about:config. So we have to construct an element to actually test if RTC
-    // is supported at the given time. 
+    // is supported at the given time.
     try {
       new RtcPeerConnection(
           {"iceServers": [ {"url":"stun:localhost"}]});
@@ -18238,9 +18238,9 @@ class RtcSessionDescription native "RTCSessionDescription,mozRTCSessionDescripti
     // the unprefixed RTCIceCandidate in Firefox (currently both are defined,
     // but one can't be used as a constructor).
     var constructorName = JS('', 'window[#]',
-        Device.isFirefox ? '${Device.propertyPrefix}RTCSessionDescription' : 
+        Device.isFirefox ? '${Device.propertyPrefix}RTCSessionDescription' :
        'RTCSessionDescription');
-    return JS('RtcSessionDescription', 
+    return JS('RtcSessionDescription',
         'new #(#)', constructorName,
         convertDartToNative_SerializedScriptValue(dictionary));
   }
@@ -19915,8 +19915,8 @@ class StorageInfo native "StorageInfo" {
   Future<StorageInfoUsage> queryUsageAndQuota(int storageType) {
     var completer = new Completer<StorageInfoUsage>();
     _queryUsageAndQuota(storageType,
-        (currentUsageInBytes, currentQuotaInBytes) { 
-          completer.complete(new StorageInfoUsage(currentUsageInBytes, 
+        (currentUsageInBytes, currentQuotaInBytes) {
+          completer.complete(new StorageInfoUsage(currentUsageInBytes,
               currentQuotaInBytes));
         },
         (error) { completer.completeError(error); });
@@ -19924,7 +19924,7 @@ class StorageInfo native "StorageInfo" {
   }
 }
 
-/** 
+/**
  * A simple container class for the two values that are returned from the
  * futures in requestQuota and queryUsageAndQuota.
  */
@@ -20367,7 +20367,7 @@ class TemplateElement extends Element native "HTMLTemplateElement" {
   @Experimental
   static Stream<DocumentFragment> get instanceCreated {
     if (_instanceCreated == null) {
-      _instanceCreated = new StreamController<DocumentFragment>();
+      _instanceCreated = new StreamController<DocumentFragment>(sync: true);
     }
     return _instanceCreated.stream;
   }
@@ -23294,7 +23294,7 @@ class _BeforeUnloadEventStreamProvider implements
   const _BeforeUnloadEventStreamProvider(this._eventType);
 
   Stream<BeforeUnloadEvent> forTarget(EventTarget e, {bool useCapture: false}) {
-    var controller = new StreamController();
+    var controller = new StreamController(sync: true);
     var stream = new _EventStream(e, _eventType, useCapture);
     stream.listen((event) {
       var wrapped = new _BeforeUnloadEvent(event);
@@ -25635,7 +25635,7 @@ class _KeyboardEventHandler extends EventStreamProvider<KeyEvent> {
   static final int _ROMAN_ALPHABET_OFFSET = "a".codeUnits[0] - "A".codeUnits[0];
 
   /** Controller to produce KeyEvents for the stream. */
-  final StreamController _controller = new StreamController();
+  final StreamController _controller = new StreamController(sync: true);
 
   static const _EVENT_TYPE = 'KeyEvent';
 
@@ -25704,7 +25704,7 @@ class _KeyboardEventHandler extends EventStreamProvider<KeyEvent> {
    * Hook up all event listeners under the covers so we can estimate keycodes
    * and charcodes when they are not provided.
    */
-  _KeyboardEventHandler.initializeAllEventListeners(this._type, this._target) : 
+  _KeyboardEventHandler.initializeAllEventListeners(this._type, this._target) :
     super(_EVENT_TYPE) {
     Element.keyDownEvent.forTarget(_target, useCapture: true).listen(
         processKeyDown);
@@ -26849,7 +26849,8 @@ class PathObserver {
     // TODO(jmesserly): if the path is empty, or the object is! Observable, we
     // can optimize the PathObserver to be more lightweight.
 
-    _values = new StreamController.broadcast(onListen: _observe,
+    _values = new StreamController.broadcast(sync: true,
+                                             onListen: _observe,
                                              onCancel: _unobserve);
 
     if (_isValid) {
@@ -29260,7 +29261,7 @@ class FixedSizeListIterator<T> implements Iterator<T> {
   final int _length;  // Cache array length for faster access.
   int _position;
   T _current;
-  
+
   FixedSizeListIterator(List<T> array)
       : _array = array,
         _position = -1,