public static LottieTask<LottieComposition> fromJsonReader(final JsonReader reader, @Nullable final String cacheKey) {
    return cache(cacheKey, () -> fromJsonReaderSync(reader, cacheKey), () -> Utils.closeQuietly(reader));
  }
Return a LottieComposition for the specified raw json string.
If loading from a file, it is preferable to use the InputStream or rawRes version.
lottie/src/main/java/com/airbnb/lottie/LottieCompositionFactory.java