code: public MediaHttpDownloader setChunkSize(int chunkSize) {
      Preconditions.checkArgument(chunkSize > 0 && chunkSize <= MAXIMUM_CHUNK_SIZE);
      this.chunkSize = chunkSize;
      return this;
    }
docs: Sets the maximum size of individual chunks that will get downloaded by single HTTP requests.
  The default value is {@link #MAXIMUM_CHUNK_SIZE}.
  
  <p>
  The maximum allowable value is {@link #MAXIMUM_CHUNK_SIZE}.
  </p>