Merge Forgotten Cleanup from CE CDM v3.5.0

This CL just updates some comments from the http://go/wvgerrit/51680.  Changes
in that CL made to oemcrypto are in the refactor CL.

Test: tested as part of http://go/ag/4674759

Change-Id: Ia619089e146ea635c5a73a53bc81973bb42b42f7

libwvdrmengine/cdm/core/test/config_test_env.cpp

@@ -89,6 +89,7 @@ const std::string kCpStagingProvisioningServiceCertificate =
 // -----------------------------------------------------------------------------
 
 // Content Protection license server (Production) data
+// Testing should not be directed at this server.
 const std::string kCpProductionLicenseServer =
     "https://widevine-proxy.appspot.com/proxy";
 // NOTE: Provider ID = staging.google.com
@@ -119,6 +120,9 @@ const std::string kCpProductionServiceCertificate =
     "250A4EB9C84AB3E6539F6B6FDF56899EA29914";
 
 // Content Protection license server (UAT) data
+// Testing should be directed to this server. The only exception
+// is when testing against a new server feature that is not yet
+// deployed to this server (which would be directed to staging).
 const std::string kCpUatLicenseServer =
     "https://proxy.uat.widevine.com/proxy";
 // NOTE: Provider ID = staging.google.com
@@ -173,6 +177,11 @@ const std::string kCpOfflineKeyId =
     "74220d6f66666c696e655f636c697032";
 
 // Content Protection license server (staging) data
+// The staging server should be used only when testing against
+// a new server. (e.g., the client has a change that requires a
+// corresponding change to the server, but the server change has
+// not yet propagated to UAT) Normal testing should always be
+// directed to UAT.
 const std::string kCpStagingLicenseServer =
     "https://proxy.staging.widevine.com/proxy";
 // NOTE: Provider ID = license.widevine.com