Merge from Widevine repo of http://go/wvgerrit/135467
The v16 state diagram says that a nonce should be included in all
license requests. The unit tests were not honoring this
requirement. This CL updates the unit tests to match the
spec.
Test: ran unit tests on luci
Bug: 186565384
Change-Id: Ib3e03593538235e2eae3da1732109f0e9bfd97bd