Enable OEMCrypto Unit Tests

This is a merge from the widevine repository of
http://go/wvgerrit/13923 Switch openssl to use the EVP interface for aes-ctr-128
http://go/wvgerrit/13979 Add Test Certificate to OEMCrypto Mock
http://go/wvgerrit/13978 Add Test Keybox to Level 3 OEMCrypto
http://go/wvgerrit/13873 Enable OEMCrypto Unit Tests

This CL adds a main program to oemcrypto_test.cpp, which filters out
tests that are not supported on the specified platform. It also adds
LoadTestKeybox to the mock. This allows oemcrypto unit tests to be run
on devices that have production keybox.  It also allows the same set
of unit tests to work on Android and on non-Android platforms.

b/18962381 Use test certificate (partial fix)
b/19867990 Separate cast receiver tests

Change-Id: If89c31530103ed85aa37d7379bd5b4dc2a927f38

libwvdrmengine/oemcrypto/include/level3.h

@@ -57,6 +57,7 @@ namespace wvoec3 {
 #define Level3_QueryKeyControl          _lcc41
 #define Level3_LoadTestKeybox           _lcc42
 #define Level3_ForceDeleteUsageEntry    _lcc43
+#define Level3_LoadTestRSAKey           _lcc45
 
 extern "C" {
 
@@ -144,6 +145,7 @@ OEMCryptoResult Level3_RewrapDeviceRSAKey(OEMCrypto_SESSION session,
 OEMCryptoResult Level3_LoadDeviceRSAKey(OEMCrypto_SESSION session,
                                         const uint8_t* wrapped_rsa_key,
                                         size_t wrapped_rsa_key_length);
+OEMCryptoResult Level3_LoadTestRSAKey();
 OEMCryptoResult Level3_GenerateRSASignature(OEMCrypto_SESSION session,
                                             const uint8_t* message,
                                             size_t message_length,