message: increasing duration of test
  was failing in FF
diff: @@ -279,7 +279,7 @@ describe("ToneBufferSource", () => {
  player.onended = () => {
  wasInvoked = true;
  };
  - }, buffer.duration * 1.1).then(() => {
  + }, buffer.duration * 2).then(() => {
  expect(wasInvoked).to.equal(true);
  });
  });
  