Revert "Remove Test Keybox Again"

This reverts commit 408509efdc.

Reason for revert: just kidding. We want to run the tests on 
old devices, too.

Change-Id: I920fa825380638122f638e057bcfbe98b5f7b301

libwvdrmengine/oemcrypto/test/oemcrypto_session_tests_helper.cpp

@@ -103,6 +103,8 @@ void SessionUtil::EnsureTestKeys() {
   switch (global_features.derive_key_method) {
     case DeviceFeatures::LOAD_TEST_KEYBOX:
       keybox_ = kTestKeybox;
+      // TODO(fredgc, b/119316243): REMOVE FOLLOWING LINE:
+      if (global_features.api_version < 14) keybox_ = kTestKeyboxForV13;
       ASSERT_EQ(OEMCrypto_SUCCESS,
                 OEMCrypto_LoadTestKeybox(
                     reinterpret_cast<const uint8_t*>(&keybox_),