static String getKeyType() {
    return "type.googleapis.com/google.crypto.tink.EcdsaPrivateKey";
  }
This key manager generates new {@code EcdsaPrivateKey} keys and produces new instances of {@code
EcdsaSignJce}.
java_src/src/main/java/com/google/crypto/tink/signature/EcdsaSignKeyManager.java