Update unit tests for v15.2

Merge from Widevine repo of http://go/wvgerrit/77609

For v15.2 we require that nonces not collide across sessions and there are
restrictions placed on the mac key's IV in LoadKeys.

Test: ran unit tests on reference code

Bug: 131325434
Bug: 131326334

Change-Id: I1bb01c30d8c15d66d762c28b57d7700c44daa835

libwvdrmengine/oemcrypto/ref/src/oemcrypto_engine_ref.cpp

@@ -182,6 +182,14 @@ time_t CryptoEngine::RollbackCorrectedOfflineTime() {
   return current_time;
 }
 
+bool CryptoEngine::NonceCollision(uint32_t nonce) {
+  for (const auto & session_pair :  sessions_) {
+    const SessionContext* session = session_pair.second;
+    if (session->NonceCollision(nonce)) return true;
+  }
+  return false;
+}
+
 OEMCrypto_HDCP_Capability CryptoEngine::config_current_hdcp_capability() {
   return config_local_display_only() ? HDCP_NO_DIGITAL_OUTPUT : HDCP_V1;
 }