Minimal implementation of Widevine MediaCAS ECMG.

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

common/test_utils.h

@@ -23,9 +23,9 @@ namespace widevine {
 // |message| is the message to be signed, and |signature| is a pointer to a
 // std::string where the signature will be stored. The caller returns ownership of
 // all paramters.
-util::Status GenerateRsaSignatureSha256Pkcs1(const std::string& pem_private_key,
-                                             const std::string& message,
-                                             std::string* signature);
+Status GenerateRsaSignatureSha256Pkcs1(const std::string& pem_private_key,
+                                       const std::string& message,
+                                       std::string* signature);
 
 }  // namespace widevine