@Override
  public void dispose() {
    mDisposable.dispose();
  }
@Test
  public void testDispose() {
    DefaultGenderPrefTracker tracker =
        new DefaultGenderPrefTracker(AnyApplication.prefs(getApplicationContext()));
    Assert.assertFalse(tracker.isDisposed());

    Assert.assertNull(tracker.getDefaultGender());
    SharedPrefsHelper.setPrefsValue(R.string.settings_key_default_emoji_gender, "woman");
    Assert.assertEquals(JavaEmojiUtils.Gender.Woman, tracker.getDefaultGender());

    tracker.dispose();
    Assert.assertTrue(tracker.isDisposed());

    SharedPrefsHelper.setPrefsValue(R.string.settings_key_default_emoji_gender, "man");
    // does not change
    Assert.assertEquals(JavaEmojiUtils.Gender.Woman, tracker.getDefaultGender());
  }