Updates also include:
- Add APIs to query current Simulcrypt channel & stream status;
- EMM format change (used only to carry fingerprinting and service
blocking info);
- Key fetcher example to use curl key fetcher.
Widevine ECM v3 is redesigned mainly based on protobuf, and supports new features including carrying fingerprinting and service blocking information. Existing clients must upgrade the Widevine CAS plugin to use the new ECM v3.