Minimal implementation of Widevine MediaCAS ECMG.

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

common/crypto_util.cc

@@ -22,8 +22,8 @@
 namespace widevine {
 namespace crypto_util {
 
-const char kEncryptionKeyLabel[] = "ENCRYPTION";
-const int kEncryptionKeySizeBits = 128;
+const char kWrappingKeyLabel[] = "ENCRYPTION";
+const int kWrappingKeySizeBits = 128;
 const char kSigningKeyLabel[] = "AUTHENTICATION";
 const int kSigningKeySizeBits = 256;
 const size_t kSigningKeySizeBytes = 32;