Implement MediaDrm offline license support in Widevine hidl service.

Merged from http://go/wvgerrit/69723.

The new APIs are getOfflineLicenseIds, getOfflineLicenseState and
removeOfflineLicense. These methods are currently stubbed out in
Widevine hidl service. This CL completes the implementation.

Test: unit tests - libwvdrmdrmplugin_hidl_test

Test: GTS
  --test com.google.android.media.gts.MediaDrmTest#testWidevineApi29

bug: 117570686
Change-Id: I96ffb75f453e36e931effefd3664b5faa8d69d30

libwvdrmengine/cdm/core/include/cdm_engine.h

@@ -212,6 +212,17 @@ class CdmEngine {
                                             CdmSecurityLevel security_level,
                                             const std::string& key_set_id);
 
+  // Get offline license status: active, release or unknown
+  virtual CdmResponseType GetOfflineLicenseState(
+      const std::string& key_set_id,
+      CdmSecurityLevel security_level,
+      CdmOfflineLicenseState* license_state);
+
+  // Remove offline license with the given key_set_id
+  virtual CdmResponseType RemoveOfflineLicense(
+      const std::string& key_set_id,
+      CdmSecurityLevel security_level);
+
   // Usage related methods for streaming licenses
   // Retrieve a random usage info from the list of all usage infos for this app
   // id.

libwvdrmengine/cdm/core/include/cdm_session.h

@@ -194,7 +194,7 @@ class CdmSession {
                                         const std::string& signature);
 
   virtual CdmResponseType SetDecryptHash(uint32_t frame_number,
-                                               const std::string& hash);
+                                         const std::string& hash);
 
   virtual CdmResponseType GetDecryptHashError(std::string* hash_error_string);
 

libwvdrmengine/cdm/core/include/device_files.h

@@ -91,6 +91,7 @@ class DeviceFiles {
                             const CdmUsageEntry& usage_entry,
                             uint32_t usage_entry_number,
                             ResponseType* result);
+
   virtual bool RetrieveLicense(
       const std::string& key_set_id, LicenseState* state,
       CdmInitData* pssh_data, CdmKeyMessage* key_request,

libwvdrmengine/cdm/core/include/wv_cdm_types.h

@@ -40,6 +40,12 @@ enum CdmKeyRequestType {
   kKeyRequestTypeRelease,
 };
 
+enum CdmOfflineLicenseState {
+  kLicenseStateActive,
+  kLicenseStateReleasing,
+  kLicenseStateUnknown,
+};
+
 enum CdmResponseType {
   NO_ERROR = 0,
   UNKNOWN_ERROR = 1,
@@ -355,6 +361,11 @@ enum CdmResponseType {
   INVALID_LICENSE_TYPE_2 = 310,
   SIGNATURE_NOT_FOUND_2 = 311,
   SESSION_KEYS_NOT_FOUND_2 = 312,
+  GET_OFFLINE_LICENSE_STATE_ERROR_1 = 313,
+  GET_OFFLINE_LICENSE_STATE_ERROR_2 = 314,
+  REMOVE_OFFLINE_LICENSE_ERROR_1 = 315,
+  REMOVE_OFFLINE_LICENSE_ERROR_2 = 316,
+  SESSION_NOT_FOUND_21 = 317,
   // Don't forget to add new values to ../test/test_printers.cpp.
 };