Handle converting maps that are null or empty

     * @see 'Adapted from https://github.com/artemyarulin/react-native-eval/blob/master/android/src/main/java/com/evaluator/react/ConversionUtil.java'

     */

    public static Map<String, String> toStringMap(@Nullable ReadableMap readableMap) {

        Map<String, String> result = new HashMap<>();

        if (readableMap == null)

            return null;

            return result;

        com.facebook.react.bridge.ReadableMapKeySetIterator iterator = readableMap.keySetIterator();

        if (!iterator.hasNextKey())

            return null;

        Map<String, String> result = new HashMap<>();

        while (iterator.hasNextKey()) {

            String key = iterator.nextKey();

            result.put(key, readableMap.getString(key));