Report key status change

Also modified PolicyEngine::CanDecrypt to use the new Keys_status_.

Bug: 19771431

Merged from Widevine CDM repo:
https://widevine-internal-review.googlesource.com/#/c/13904/

Change-Id: If7fb7fa45ecf9ff4e65278cda00ad7230b57f50b

libwvdrmengine/cdm/core/include/policy_engine.h

@@ -3,6 +3,7 @@
 #ifndef WVCDM_CORE_POLICY_ENGINE_H_
 #define WVCDM_CORE_POLICY_ENGINE_H_
 
+#include <map>
 #include <string>
 
 #include "license_protocol.pb.h"
@@ -59,6 +60,8 @@ class PolicyEngine {
   // Used for notifying the Policy Engine of resolution changes
   virtual void NotifyResolution(uint32_t width, uint32_t height);
 
+  virtual void NotifySessionExpiration();
+
   virtual CdmResponseType Query(CdmQueryMap* key_info);
 
   virtual const LicenseIdentification& license_id() { return license_id_; }
@@ -105,15 +108,19 @@ class PolicyEngine {
 
   void UpdateRenewalRequest(int64_t current_time);
 
+  // Notifies updates in keys information and fire OnKeysChange event if
+  // key changes.
+  void NotifyKeysChange(CdmKeyStatus new_status);
+
   // Notifies updates in expiry time and fire OnExpirationUpdate event if
   // expiry time changes.
   void NotifyExpirationUpdate();
 
   // These setters are for testing only. Takes ownership of the pointers.
   void set_clock(Clock* clock);
+  void set_max_res_engine(MaxResEngine* max_res_engine);
 
   LicenseState license_state_;
-  bool can_decrypt_;
 
   // This is the current policy information for this license. This gets updated
   // as license renewals occur.
@@ -142,7 +149,10 @@ class PolicyEngine {
   CdmSessionId session_id_;
   WvCdmEventListener* event_listener_;
 
-  MaxResEngine max_res_engine_;
+  scoped_ptr<MaxResEngine> max_res_engine_;
+
+  std::map<KeyId, CdmKeyStatus> keys_status_;
+
   scoped_ptr<Clock> clock_;
 
   CORE_DISALLOW_COPY_AND_ASSIGN(PolicyEngine);