private void setIndexMemState(IndexMemState state) {
    properties.setProperty(StoreConfig.storeIndexMemStateName, state.name());
    properties.setProperty("store.set.file.permission.enabled", Boolean.toString(true));
    config = new StoreConfig(new VerifiableProperties(properties));
  }
@param state the value for {@link StoreConfig#storeIndexMemStateName}
ambry-store/src/test/java/com/github/ambry/store/IndexSegmentTest.java