public Preference<Boolean> getBoolean(@StringRes int prefKey, @BoolRes int defaultValue) {
    return mRxSharedPreferences.getBoolean(
        mResources.getString(prefKey), mResources.getBoolean(defaultValue));
  }
@Test
  public void testSetupFallbackDictionaryToFalseIfWasNotSetBefore() {
    SharedPrefsHelper.setPrefsValue(RxSharedPrefs.CONFIGURATION_VERSION, 11);

    SharedPreferences preferences =
        PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
    Assert.assertFalse(preferences.contains("settings_key_always_use_fallback_user_dictionary"));

    new RxSharedPrefs(getApplicationContext(), this::testRestoreFunction);

    Assert.assertTrue(preferences.contains("settings_key_always_use_fallback_user_dictionary"));
    Assert.assertFalse(
        preferences.getBoolean("settings_key_always_use_fallback_user_dictionary", true));
  }