[ Merge of http://go/wvgerrit/153489 ]
OEMCrypto does not provide an API for retrieving the system ID when
the TEE uses a built-in DRM certificate (provisioning 1.0). New OEMs
and Android devices do not use prov 1.0; however, the Zimperium CDM
(at least the tests) use a built-in certificate and are failing
certain tests because of the missing system ID. To address this
failure; the CDM SystemIdExtractor has been updated to return a null
system ID.
Bug: 235879962
Test: system_id_extractor_unittest
Change-Id: Ib4c2bd75a7825967b0aa9e31e144184ae18fe8fb
6024987733