message: Fix round-trip failure of AES256_GCM_HKDF_4KB on Android 23.
diff: @@ -251,8 +251,14 @@ public final class AesGcmHkdfStreaming extends NonceBasedStreamingAead {
  keySpec,
  paramsForSegment(noncePrefix, encryptedSegments, isLastSegment));
  encryptedSegments++;
  + // `update(nonEmpty)`, `doFinal(empty)` is known to cause problems on Android 23.
  + // See https://github.com/google/tink/issues/229
  + if (part2.hasRemaining()) {
  cipher.update(part1, ciphertext);
  cipher.doFinal(part2, ciphertext);
  + } else {
  + cipher.doFinal(part1, ciphertext);
  + }
  }
  @Override
  