Merge from widevine repo of http://go/wvgerrit/24421
A nonce generation error for a certificate provisioning request had a
generic name Error2. However, this is an actionable error by the
application: the application should wait 1 second and try again.
Therefore it deserves a more descriptive name.
bug: 35926133
bug: 35879493
Change-Id: I6c87a5a762cb970c9530a55c993d7acbed773a00
14c3a3865a