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/core/src/cdm_session.cpp

@@ -382,11 +382,11 @@ CdmResponseType CdmSession::GenerateKeyRequest(
     }
 
     std::vector<video_widevine::SubLicense> embedded_key_data =
-        init_data.ExtractEmbeddedKeys();
+        init_data.ExtractSublicenseKeys();
     for (size_t i = 0; i < embedded_key_data.size(); ++i) {
       CdmResponseType sts = crypto_session_->AddSubSession(
           embedded_key_data[i].sub_session_key_id(),
-          init_data.ExtractGroupMasterKeyId());
+          embedded_key_data[i].group_id());
       if (NO_ERROR != sts) {
         LOGE("CdmSession::GenerateKeyRequest: Unable to generate sub session");
         return sts;