@Override
  public boolean nextBoolean() throws IOException {
    return delegate.readBoolean();
  }
Gson library reads numbers lazily when using generic
{@link com.google.gson.internal.bind.TypeAdapters#JSON_ELEMENT} type adapter.
Number is read as string and then wrapped inside {@link LazilyParsedNumber}. This inefficiency
should only occur if reading numbers with generic JSON element API
and not using generated type adapters.
@see LazilyParsedNumber
@see com.google.gson.internal.bind.TypeAdapters#JSON_ELEMENT
mongo/src/org/immutables/mongo/bson4gson/BsonReader.java