@Deprecated // Unused Interface Method. Will be removed.
  default MessageLite newKey(ByteString serializedKeyFormat) throws GeneralSecurityException {
    throw new UnsupportedOperationException();
  }
Generates a new key according to specification in {@code serializedKeyFormat}, which must be a
serialized key format protocol buffer handled by this manager.

<p>This method is not used by Tink anymore. It does not need to be implemented.

@return the new generated key
@throws GeneralSecurityException if the specified format is wrong or not supported
@deprecated Use {@code newKeyData(serializedKeyFormat)} instead.
java_src/src/main/java/com/google/crypto/tink/KeyManager.java