message: Explicitly specify that the PrimitiveFactory is from KeyTypeManager.
  I hope this fixes a bug on some android versions.
diff: @@ -45,7 +45,7 @@ public final class AesGcmKeyManager extends KeyTypeManager<AesGcmKey> {
  AesGcmKeyManager() {
  super(
  AesGcmKey.class,
  - new PrimitiveFactory<Aead, AesGcmKey>(Aead.class) {
  + new KeyTypeManager.PrimitiveFactory<Aead, AesGcmKey>(Aead.class) {
  @Override
  public Aead getPrimitive(AesGcmKey key) throws GeneralSecurityException {
  return new AesGcmJce(key.getKeyValue().toByteArray());
  