message: Restricting KeyManagerImpl.java to only be visible within com.google.crypto.tink.
diff: @@ -26,13 +26,9 @@ import java.security.GeneralSecurityException;
  *
  * <p>Choosing {@code PrimitiveT} equal to {@link java.lang.Void} is valid; in this case the
  * functions {@link #getPrimitive} will throw if invoked.
  - *
  - * <p>TODO(tholenst): Visibility restrict to package visibility once all key managers are migrated
  - * to KeyTypeManager's.
  */
  @Alpha
  -public class KeyManagerImpl<PrimitiveT, KeyProtoT extends MessageLite>
  - implements KeyManager<PrimitiveT> {
  +class KeyManagerImpl<PrimitiveT, KeyProtoT extends MessageLite> implements KeyManager<PrimitiveT> {
  public KeyManagerImpl(
  KeyTypeManager<KeyProtoT> keyTypeManager, Class<PrimitiveT> primitiveClass) {
  if (!keyTypeManager.supportedPrimitives().contains(primitiveClass)
  