Merge from Widevine repo of http://go/wvgerrit/125744
The OEMCrypto tests use a fixed RSA key. This will be loaded using
OEMCrypto_LoadTestRSAKey. This adds that key in DER format. This key
was stored in the kTestRSAPKCS8PrivateKeyInfo2_2048 variable in the
code.
Bug: 202994773
Test: test only data
Change-Id: I372a45c48ddeff5149f3685640fa09ff569a696a