Merge Widevine CDM-Side Core Changes

This is a combined merge of several small changes to the core in the
Widevine CDM repository:

http://go/wvgerrit/10941
  Rename privacy_crypto to allow more variants.

http://go/wvgerrit/11530
  Add Missing Header to properties.h

http://go/wvgerrit/11531
  More Loosely Couple CdmEngine and CdmSession

Change-Id: I5b3f738ae495ab267da1440421dd7aa6f7860194

libwvdrmengine/cdm/core/include/privacy_crypto.h

@@ -55,7 +55,7 @@ class RsaPublicKey {
   bool Encrypt(const std::string& plaintext,
                std::string* ciphertext);
 
-  // Verify RSSASSA-PSS signature. Caller retains ownership of all parameters.
+  // Verify RSASSA-PSS signature. Caller retains ownership of all parameters.
   // Returns true if validation succeeds, false otherwise.
   bool VerifySignature(const std::string& message,
                        const std::string& signature);