Make RTC work on Firefox (mostly).

sdk/lib/html/dart2js/html_dart2js.dart

 /// The Dart HTML library.
 library dart.dom.html;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:_collection-dev' hide Symbol;
 import 'dart:html_common';
 import 'dart:indexed_db';
 import 'dart:isolate';
 import 'dart:json' as json;
@@ skipping 17268 matching lines @@
 // Copyright (c) 2013, 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.
 
 
 @DomName('RTCIceCandidate')
 @SupportedBrowser(SupportedBrowser.CHROME)
 @Experimental
 class RtcIceCandidate native "RTCIceCandidate" {
   factory RtcIceCandidate(Map dictionary) {
-    return JS('RtcIceCandidate', 'new RTCIceCandidate(#)',
+    // TODO(efortuna): Remove this check if when you can actually construct with
+    // 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' : 
+        'RTCIceCandidate');
+    return JS('RtcIceCandidate', 'new #(#)', constructorName,
         convertDartToNative_SerializedScriptValue(dictionary));
   }
 
   @DomName('RTCIceCandidate.candidate')
   @DocsEditable
   final String candidate;
 
   @DomName('RTCIceCandidate.sdpMLineIndex')
   @DocsEditable
   final int sdpMLineIndex;
@@ skipping 39 matching lines @@
   }
 
   /**
    * Checks if Real Time Communication (RTC) APIs are supported and enabled on
    * the current platform.
    */
   static bool get supported {
     // 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 at the given time.
+    // is supported at the given time. 
     try {
-      var c = new RtcPeerConnection({"iceServers": [ {"url":"stun:foo.com"}]});
-      return c is RtcPeerConnection;
-    } catch (_) {}
+      new RtcPeerConnection(
+          {"iceServers": [ {"url":"stun:localhost"}]});
+      return true;
+    } catch (_) { return false;}
     return false;
   }
   Future<RtcSessionDescription> createOffer([Map mediaConstraints]) {
     var completer = new Completer<RtcSessionDescription>();
     _createOffer(
         (value) { completer.complete(value); },
         (error) { completer.completeError(error); }, mediaConstraints);
     return completer.future;
   }
 
@@ skipping 262 matching lines @@
 
   @DomName('RTCPeerConnection.onremovestream')
   @DocsEditable
   Stream<MediaStreamEvent> get onRemoveStream => removeStreamEvent.forTarget(this);
 
   @DomName('RTCPeerConnection.onsignalingstatechange')
   @DocsEditable
   Stream<Event> get onSignalingStateChange => signalingStateChangeEvent.forTarget(this);
 
 }
-
-
 // Copyright (c) 2013, 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.
 
 
 @DomName('RTCSessionDescription')
 @SupportedBrowser(SupportedBrowser.CHROME)
 @Experimental
 class RtcSessionDescription native "RTCSessionDescription" {
   factory RtcSessionDescription(Map dictionary) {
-    return JS('RtcSessionDescription', 'new RTCSessionDescription(#)',
+    // TODO(efortuna): Remove this check if when you can actually construct with
+    // 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' : 
+       'RTCSessionDescription');
+    return JS('RtcSessionDescription', 
+        'new #(#)', constructorName,
         convertDartToNative_SerializedScriptValue(dictionary));
   }
 
   @DomName('RTCSessionDescription.sdp')
   @DocsEditable
   String sdp;
 
   @DomName('RTCSessionDescription.type')
   @DocsEditable
   String type;
@@ skipping 10693 matching lines @@
       _position = nextPosition;
       return true;
     }
     _current = null;
     _position = _array.length;
     return false;
   }
 
   T get current => _current;
 }