Map typed arrays to lists for now.

sdk/lib/web_audio/dart2js/web_audio_dart2js.dart

Index: sdk/lib/web_audio/dart2js/web_audio_dart2js.dart
diff --git a/sdk/lib/web_audio/dart2js/web_audio_dart2js.dart b/sdk/lib/web_audio/dart2js/web_audio_dart2js.dart
index 40c0d75f85993ea6e7f5a8eb4a7da6c7c69fad87..97aaa0ebe2d84924c6cc6c4725e58af230aff1c1 100644
--- a/sdk/lib/web_audio/dart2js/web_audio_dart2js.dart
+++ b/sdk/lib/web_audio/dart2js/web_audio_dart2js.dart
@@ -84,7 +84,9 @@ class AudioBuffer native "*AudioBuffer" {
 
   @DomName('AudioBuffer.getChannelData')
   @DocsEditable
-  Float32Array getChannelData(int channelIndex) native;
+  @Returns('Float32Array')
+  @Creates('Float32Array')
+  List<double> getChannelData(int channelIndex) native;
 }
 // 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
@@ -834,7 +836,9 @@ class WaveShaperNode extends AudioNode native "*WaveShaperNode" {
 
   @DomName('WaveShaperNode.curve')
   @DocsEditable
-  Float32Array curve;
+  @Returns('Float32Array')
+  @Creates('Float32Array')
+  List<double> curve;
 }
 // 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