Update LoadTestKeybox

Merge from Widevine repo of http://go/wvgerrit/41662

This CL updates oemcrypto unit tests to use the new test keybox.

bug: 69552641 Update OEMCrypto_LoadTestKeybox

test: Unit tests compile and run -- many tests won't pass until merged
with vendor code

Change-Id: I73bdca3958b2c985d4c61801aa95807a2e6d4299

libwvdrmengine/oemcrypto/mock/src/oemcrypto_engine_mock.h

@@ -47,7 +47,9 @@ class CryptoEngine {
     return root_of_trust_.InstallKeybox(keybox, keybox_length);
   }
 
-  void UseTestKeybox() { root_of_trust_.UseTestKeybox(); }
+  bool UseTestKeybox(const uint8_t* keybox_data, size_t keybox_length) {
+    return root_of_trust_.UseTestKeybox(keybox_data, keybox_length);
+  }
 
   bool LoadTestRsaKey() { return root_of_trust_.LoadTestRsaKey(); }