Add Max-Res Decode Engine to CDM Core

(This is a port of http://go/wvgerrit/11555 from the Widevine CDM
repo.)

Bug: 16034599
Change-Id: Ie69afac7d89e27623adbc84d2baebccf1d1ba6e6

libwvdrmengine/cdm/core/include/policy_engine.h

@@ -6,6 +6,7 @@
 #include <string>
 
 #include "license_protocol.pb.h"
+#include "max_res_engine.h"
 #include "wv_cdm_types.h"
 
 namespace wvcdm {
@@ -13,13 +14,14 @@ namespace wvcdm {
 using video_widevine_server::sdk::LicenseIdentification;
 
 class Clock;
+class CryptoSession;
 class PolicyEngineTest;
 
 // This acts as an oracle that basically says "Yes(true) you may still decrypt
 // or no(false) you may not decrypt this data anymore."
 class PolicyEngine {
  public:
-  PolicyEngine();
+  explicit PolicyEngine(CryptoSession* crypto_session);
   virtual ~PolicyEngine();
 
   // The value returned should be taken as a hint rather than an absolute
@@ -27,7 +29,7 @@ class PolicyEngine {
   // UpdateLicense/OnTimerEvent/BeginDecryption and may be out of sync
   // depending on the amount of time elapsed. The current decryption
   // status is not calculated to avoid overhead in the decryption path.
-  virtual bool can_decrypt() { return can_decrypt_; }
+  virtual bool CanDecrypt(const KeyId& key_id);
 
   // OnTimerEvent is called when a timer fires. It notifies the Policy Engine
   // that the timer has fired and that it should check whether any events have
@@ -118,11 +120,12 @@ class PolicyEngine {
   int64_t next_renewal_time_;
   int64_t policy_max_duration_seconds_;
 
+  MaxResEngine max_res_engine_;
   Clock* clock_;
 
   // For testing
   friend class PolicyEngineTest;
-  PolicyEngine(Clock* clock);
+  PolicyEngine(CryptoSession* crypto_session, Clock* clock);
 
   CORE_DISALLOW_COPY_AND_ASSIGN(PolicyEngine);
 };