Certificate provisioning verification

bug: 8620943

This is a merge of changes made to the Widevine CDM
repository during certificate provisioning verification.

The following changes are included:

Fixes for certificate based licensing
https://widevine-internal-review.googlesource.com/#/c/5162/

Base64 encode and decode now handles non-multiple of 24-bits input
https://widevine-internal-review.googlesource.com/#/c/4981/

Fixed issues with device provisioning response handling
https://widevine-internal-review.googlesource.com/#/c/5153/

Persistent storage to support device certificates
https://widevine-internal-review.googlesource.com/#/c/5161/

Enable loading of certificates
https://widevine-internal-review.googlesource.com/#/c/5172/

Provide license server url
https://widevine-internal-review.googlesource.com/#/c/5173/

Change-Id: I0c032c1ae0055dcc1a7a77ad4b0ea0898030dc7d

libwvdrmengine/mediadrm/src/WVDrmPlugin.cpp

@@ -145,13 +145,16 @@ status_t WVDrmPlugin::getKeyRequest(
   }
 
   CdmKeyMessage keyRequest;
+  string cdmDefaultUrl;
 
   CdmResponseType res = mCDM->GenerateKeyRequest(cdmSessionId, cdmInitData,
                                                  cdmLicenseType,
-                                                 cdmParameters, &keyRequest);
+                                                 cdmParameters, &keyRequest,
+                                                 &cdmDefaultUrl);
 
   if (isCdmResponseTypeSuccess(res)) {
     defaultUrl.clear();
+    defaultUrl.setTo(cdmDefaultUrl.data(), cdmDefaultUrl.size());
 
     request.clear();
     request.appendArray(reinterpret_cast<const uint8_t*>(keyRequest.data()),