Add the encrypted flag for the KeyPairGenerator and the KeyStore so that
applications can choose to allow entries when there is no lockscreen.
(partial cherry pick from commit 2eeda7286f)
Bug: 8122243
Change-Id: I5ecd9251ec79ec53a3b68c0fff8dfba10873e36e
This allows end-users to generate keys in the keystore without the
private part of the key ever needing to leave the device. The generation
process also generates a self-signed certificate.
Change-Id: I114ffb8e0cbe3b1edaae7e69e8aa578cb835efc9
