Do not fall back to L3 if L1 has test keybox

[ Merged of go/wvgerrit/186370 ]

CDM by default allows test keybox from device side.

Bug: 299987160
Bug: 301669353
Change-Id: I06f1936ccd068eb71364a5a8931970954233b686

libwvdrmengine/cdm/core/test/test_base.cpp

@@ -205,7 +205,6 @@ TestCryptoSession::TestCryptoSession(metrics::CryptoMetrics* crypto_metrics,
 
 void TestCryptoSession::MaybeInstallTestKeybox() {
   if (IsTestKeyboxNeeded()) {
-    CryptoSession::SetAllowTestKeybox(true);
     ReinitializeForTest();
     WvCdmTestBase::InstallTestRootOfTrust();
   }