chromium/media/test/data/webaudio_oscillator.html

<!DOCTYPE html>
<title>WebAudio Oscillator</title>
<script>
var context = new window.AudioContext();
var oscillator = context.createOscillator();
oscillator.connect(context.destination);
function StartOscillator() {
  oscillator.start();
  return 'OK';
}
</script>