code: public MediaHttpUploader setChunkSize(int chunkSize) {
      Preconditions.checkArgument(chunkSize > 0 && chunkSize % MINIMUM_CHUNK_SIZE == 0, "chunkSize"
          + " must be a positive multiple of " + MINIMUM_CHUNK_SIZE + ".");
      this.chunkSize = chunkSize;
      return this;
    }
docs: Sets the maximum size of individual chunks that will get uploaded by single HTTP requests. The
  default value is {@link #DEFAULT_CHUNK_SIZE}.
  
  <p>
  The minimum allowable value is {@link #MINIMUM_CHUNK_SIZE} and the specified chunk size must be
  a multiple of {@link #MINIMUM_CHUNK_SIZE}.
  </p>