@BeforeTemplate
    public KeysetHandle beforeTemplate() throws GeneralSecurityException {
      return KeysetHandle.generateNew(MacKeyTemplates.HMAC_SHA512_512BITTAG);
    }
If users first create a binary keyset reader from a byte[], then call readNoSecret, we can
simply call the new function directly without any parsing.
java_src/tools/refaster/java/com/google/tink1_templates/AllChanges.java