Minimal implementation of Widevine MediaCAS ECMG.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=226515998

protos/public/media_cas.proto

@@ -11,13 +11,6 @@ syntax = "proto2";
 
 package widevine.cas;
 
-// Encrypt/decrypt mode.
-enum CasCryptoMode {
-  CRYPTO_MODE_UNSPECIFIED = 0;
-  CTR = 1;
-  CBC = 2;
-};
-
 // Widevine private data in the CA descriptor.
 message CaDescriptorPrivateData {
   // Provider name.