This propagates the concept that 0 is an invalid crypto operation
handle to the outside of AndroidKeyStore abstraction.
Bug: 20864436
Change-Id: I1e5abb66c5d41d8fc32aac44372495a708c2b6e2
This adds AndroidKeyStore.getKeyStoreOperationHandle method which can
be used to obtain the KeyStore operation handle corresponding to the
provided JCA cryto primitive (provided it's backed by
AndroidKeyStore).
Bug: 18088752
Change-Id: Iaa3b6f9b2281b2ec2de8fd5946d353dc7fdb3d2d