NativeCrypto: special case for empty cipher list
NativeCrypto: special case for empty cipher list

For the Java language, setting an empty cipher list is not an error but
it's an error in OpenSSL. However, the underlying API actually updates
the cipher list to an empty string as intended. So we need to handle
this special case by clearing the error stack and making sure that our
expectation is satisfied.

Bug: 21195269
Change-Id: Id21792215513f4e0d6e051160f69e5f830d39015

google/conscrypt,google/conscrypt,google/conscrypt,google/conscrypt,google/conscrypt,google/conscrypt