Allow a service certificate to be specified for provisioning

[ Merge of http://go/wvgerrit/48400 ]

Client identification information has recently been enabled in
provisioning messages. For privacy concerns this information
is being encrypted with a default service certificate.
Apps need to be able to override the default one to allow
for provisioning with third party provisioning services.

Bug: 78420508
Test: WV unit, integration tests
      New WvCdmRequestLicenseTest.ProvisioningTestWithServiceCertificate test
      GTS MediaDrmTestCases

Change-Id: Iee61ad47d33ce011efbea4eb90f7e4b1f032d15f

libwvdrmengine/cdm/test/cdm_extended_duration_test.cpp

@@ -40,6 +40,7 @@ const uint32_t kMinute = 60;
 const uint32_t kClockTolerance = 10;
 
 const uint32_t kMaxUsageTableSize = 50;
+const std::string kEmptyServiceCertificate;
 
 // Default license server, can be configured using --server command line option
 // Default key id (pssh), can be configured using --keyid command line option
@@ -443,8 +444,8 @@ class WvCdmExtendedDurationTest : public WvCdmTestBase {
     std::string cert_authority, cert, wrapped_key;
 
     status = decryptor_.GetProvisioningRequest(
-        cert_type, cert_authority, kDefaultCdmIdentifier, &key_msg_,
-        &provisioning_server_url);
+        cert_type, cert_authority, kDefaultCdmIdentifier,
+        kEmptyServiceCertificate, &key_msg_, &provisioning_server_url);
     EXPECT_EQ(NO_ERROR, status);
     if (NO_ERROR != status) return;
     EXPECT_EQ(provisioning_server_url, g_config->provisioning_server());