public static void testEncryptSingleBytes(StreamingAead ags, int plaintextSize) throws Exception {
    testEncryptSingleBytesWithChannel(ags, plaintextSize);
    testEncryptSingleBytesWithStream(ags, plaintextSize);
  }
Encrypts and decrypts some plaintext in a stream using skips and checks that the expected
plaintext is returned for the parts not skipped.

@param ags the StreamingAead test object.
@param firstSegmentOffset number of bytes prepended to the ciphertext stream.
@param plaintextSize the size of the plaintext
@param chunkSize decryption skips and reads chunks of this size.
java_src/src/main/java/com/google/crypto/tink/testing/StreamingTestUtil.java