code: private synchronized Producer<CloseableReference<CloseableImage>>
    getLocalVideoFileFetchSequence() {
      if (mLocalVideoFileFetchSequence == null) {
        LocalVideoThumbnailProducer localVideoThumbnailProducer =
            mProducerFactory.newLocalVideoThumbnailProducer();
        mLocalVideoFileFetchSequence =
            newBitmapCacheGetToBitmapCacheSequence(localVideoThumbnailProducer);
      }
      return mLocalVideoFileFetchSequence;
    }
docs: Bitmap cache get -> thread hand off -> multiplex -> bitmap cache ->
  local video thumbnail