Fixing up Navigator.getUserMedia.

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;
+
+/// @domName $DOMNAME; @docsEditable true
+class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
+
+$if DART2JS
+  /// @domName Navigator.language; @docsEditable true
+  String get language => JS('String', '#.language || #.userLanguage', this,
+      this);
+$endif
+
+  /**
+   * Gets a stream (video and or audio) from the local computer.
+   *
+   * Use [MediaStream.supported] to check if this is supported by the current
+   * platform.
+   *
+   * Example use:
+   *
+   *     window.navigator.getUserMedia(audio:true, video: true).then((stream) {
+   *       var video = new VideoElement()
+   *         ..autoplay = true
+   *         ..src = Url.createObjectUrl(stream);
+   *       document.body.append(video);
+   *     });
+   *
+   * See also:
+   * * [MediaStream.supported]
+   */
+  @SupportedBrowser(SupportedBrowser.CHROME)
+  @Experimental()
+  Future<LocalMediaStream> getUserMedia({bool audio=false, bool video=false}) {
+    var completer = new Completer<LocalMediaStream>();
+    var options = {
+      'audio': audio,
+      'video': video
+    };
+$if DART2JS
+    _ensureGetUserMedia();
+    this._getUserMedia(convertDartToNative_Dictionary(options),
+      (stream) {
+        completer.complete(stream);
+      },
+      (error) {
+        completer.completeError(error);
+      });
+$else
+    this._getUserMedia(options,
+      (stream) {
+        completer.complete(stream);
+      },
+      (error) {
+        completer.completeError(error);
+      });
+$endif
+    return completer.future;
+  }
+
+$if DART2JS
+  _ensureGetUserMedia() {
+    if (JS('bool', '!(#.getUserMedia)', this)) {
+      JS('void', '#.getUserMedia = '
+          '(#.getUserMedia || #.webkitGetUserMedia || #.mozGetUserMedia ||'
+          '#.msGetUserMedia)', this, this, this, this, this);
+    }
+  }
+
+  @JSName('getUserMedia')
+  void _getUserMedia(options, _NavigatorUserMediaSuccessCallback success,
+      _NavigatorUserMediaErrorCallback error) native;
+$endif
+
+$!MEMBERS
+}