Don't use => on void functions.

sdk/lib/web_audio/dartium/web_audio_dartium.dart

 /**
  * High-fidelity audio programming in the browser.
  */
 library dart.dom.web_audio;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:_internal';
 import 'dart:html';
 import 'dart:html_common';
@@ skipping 671 matching lines @@
       return;
     }
     if ((output is int) && (destination_OR_output is AudioParam) && input == null) {
       _blink.BlinkAudioNode.instance.disconnect_Callback_2_(this, destination_OR_output, output);
       return;
     }
     throw new ArgumentError("Incorrect number or type of arguments");
   }
 
   @DomName('AudioNode.connect')
-  void connectNode(AudioNode destination, [int output = 0, int input = 0]) =>
-      _connect(destination, output, input);
+  void connectNode(AudioNode destination, [int output = 0, int input = 0]) {
+    _connect(destination, output, input);
+  }
 
   @DomName('AudioNode.connect')
-  void connectParam(AudioParam destination, [int output = 0]) =>
-      _connect(destination, output);
+  void connectParam(AudioParam destination, [int output = 0]) {
+    _connect(destination, output);
+  }
 }
 // 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.
 
 // WARNING: Do not edit - generated code.
 
 
 @DocsEditable()
 @DomName('AudioParam')
@@ skipping 820 matching lines @@
   
   @DomName('WaveShaperNode.oversample')
   @DocsEditable()
   String get oversample => _blink.BlinkWaveShaperNode.instance.oversample_Getter_(this);
   
   @DomName('WaveShaperNode.oversample')
   @DocsEditable()
   set oversample(String value) => _blink.BlinkWaveShaperNode.instance.oversample_Setter_(this, value);
   
 }