Add DRM reprovisioning request generation

[ Merge of http://go/wvgerrit/192010 ]

Updates the CDM to add support for DRM reprovisioning request creation.
- Load the baked-in certificate for use as the client token.
- Add functions to build and sign a drm reprovisioning request.
- Update the Rikers L3 OEMCrypto implementation to support signing
  provisioning requests and getting embedded certificate.
- Update client id token to handle DRM reprovisioning.
- Add OEMCrypto function to load the baked-in device certificate in
  Rikers CDMs and stubs for non-Rikers CDMs.
- Add dynamic adapter support for getting embedded device certificate
  only on L3.

Bug: 305093063
Test: WVTS
Change-Id: I9a0ecf95e27213b046f03baa0781fb164179323b

libwvdrmengine/cdm/core/include/crypto_session.h

@@ -112,6 +112,9 @@ class CryptoSession {
   // Only valid for OEM certificate-based based devices.
   virtual CdmResponseType GetTokenFromOemCert(
       RequestedSecurityLevel requested_security_level, std::string* oem_cert);
+  // Retrieves the embedded public certificate from OEMCrypto.
+  // Only valid for L3 devices with embedded (baked-in) certificates.
+  virtual CdmResponseType GetTokenFromEmbeddedCertificate(std::string* token);
 
   // The overloaded methods with |requested_level| may be called
   // without a preceding call to Open. The other method must call Open first.