Add basic handling for entitlement keys in a license.

Merge from Widevine repo of http://go/wvgerrit/41834

Key rotation is not yet supported.

The key statuses are updated from a license. The
mechanism expects content keys tro come in a license.
For entitlement licenses, the content keys come in the
init_data.

This code does not yet support the key rotation event.
(A new pssh with wrapped keys is a passed to the cdm)
The policy engine/key status mechanism needs to be
updated to handle updated from the init_data.

For now, the cdm builds a license with a key container
with the content keys and used that to call
PolicyEngine::SetLicense to setup the policy engine
and key statuses.

Bug: 64003606
Bug: 70334840

Test: In child CL
Change-Id: Ibf46a18f5321cab4ff6f1778ba30527942c8021f

libwvdrmengine/cdm/metrics/src/metrics_collections.cpp

@@ -196,6 +196,9 @@ CryptoMetrics::CryptoMetrics() :
     oemcrypto_load_device_rsa_key_(
         "/drm/widevine/oemcrypto/load_device_rsa_key/time",
         "oemcrypto_error"),
+    oemcrypto_load_entitled_keys_(
+            "/drm/widevine/oemcrypto/load_entitled_keys/time",
+            "oemcrypto_error"),
     oemcrypto_load_keys_(
         "/drm/widevine/oemcrypto/load_keys/time",
         "oemcrypto_error"),
@@ -277,6 +280,7 @@ void CryptoMetrics::Serialize(MetricsGroup* metrics) {
   oemcrypto_is_anti_rollback_hw_present_.Serialize(&serializer);
   oemcrypto_is_keybox_valid_.Serialize(&serializer);
   oemcrypto_load_device_rsa_key_.Serialize(&serializer);
+  oemcrypto_load_entitled_keys_.Serialize(&serializer);
   oemcrypto_load_keys_.Serialize(&serializer);
   oemcrypto_max_hdcp_capability_.Serialize(&serializer);
   oemcrypto_max_number_of_sessions_.Serialize(&serializer);