Revert "Changes for webkit roll 148757-149482"

tools/dom/templates/html/impl/impl_Navigator.darttemplate

 // 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 $LIBRARYNAME;
 
 $(ANNOTATIONS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
 
 $if DART2JS
   @DomName('Navigator.language')
@@ skipping 12 matching lines @@
    *
    *     window.navigator.getUserMedia(audio: true, video: true).then((stream) {
    *       var video = new VideoElement()
    *         ..autoplay = true
    *         ..src = Url.createObjectUrl(stream);
    *       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 
+   * map, but passing in `true` will provide a LocalMediaStream 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 
    * writing, here is an example providing more constraints.
    *
    *     window.navigator.getUserMedia(
    *         audio: true, 
    *         video: {'mandatory': 
    *                    { 'minAspectRatio': 1.333, 'maxAspectRatio': 1.334 },
    *                 'optional': 
    *                    [{ 'minFrameRate': 60 },
    *                     { 'maxWidth': 640 }]
    *     });
    *
    * See also:
    * * [MediaStream.supported]
    */
   @DomName('Navigator.webkitGetUserMedia')
   @SupportedBrowser(SupportedBrowser.CHROME)
   @Experimental
-  Future<MediaStream> getUserMedia({audio: false, video: false}) {
-    var completer = new Completer<MediaStream>();
+  Future<LocalMediaStream> getUserMedia({audio: false, video: false}) {
+    var completer = new Completer<LocalMediaStream>();
     var options = {
       'audio': audio,
       'video': video
     };
 $if DART2JS
     _ensureGetUserMedia();
     this._getUserMedia(convertDartToNative_SerializedScriptValue(options),
       (stream) {
         completer.complete(stream);
       },
@@ skipping 21 matching lines @@
     }
   }
 
   @JSName('getUserMedia')
   void _getUserMedia(options, _NavigatorUserMediaSuccessCallback success,
       _NavigatorUserMediaErrorCallback error) native;
 $endif
 
 $!MEMBERS
 }