Adds multiple files to the file store.

    Args:
      hash_id_metadatas: A dictionary mapping hash ids to file metadata (a tuple
        of hash client path and blob references).

def AddFiles(self, hash_id_metadatas):
    """Adds multiple files to the file store.

    Args:
      hash_id_metadatas: A dictionary mapping hash ids to file metadata (a tuple
        of hash client path and blob references).
    """
    for hash_id, metadata in iteritems(hash_id_metadatas):
      self.AddFile(hash_id, metadata)