From the Widevine CDM repository: https://widevine-internal-review.googlesource.com/#/c/9183/ This adds unit tests for RSA signing with PKCS1 block type 1. It also adds a reference implementation. This is part of OEMCrypto v9. Change-Id: I2a40dbff65f6e09d75f16ae048499512f60c168d