Enable SPOIDs in Treble Widevine Glue Layer

Adds code to the Widevine Glue Layer that drives the generation and use
of SPOIDs on platforms that support SPOIDs. (All devices whose first
release is Android O or later.) Note that this only applies to the new,
Treble-ized API. If the Widevine DRM Plugin is accessed through the old
API, it will not use SPOIDs. This is by design because the old API does
not provide an application package name, so SPOID generation is no
better than the existing, origin-based solution.

Bug: 27101531
Test: Unit tests
Test: GTS tests
Test: Google Play
Change-Id: I80f79fca84065105e218e9070a1d5299c8e33500

libwvdrmengine/mediadrm/include_hidl/WVDrmPlugin.h

@@ -309,17 +309,39 @@ struct WVDrmPlugin : public IDrmPlugin, IDrmPluginListener,
     const std::string mEmptyString;
   } mPropertySet;
 
-  std::string mAppPackageName;
+  class CdmIdentifierBuilder {
+   public:
+    CdmIdentifierBuilder();
+
+    const CdmIdentifier& get_identifier();
+    const std::string& get_device_unique_id();
+
+    bool set_device_id(const std::string& id);
+
+    const std::string& app_package_name() { return mAppPackageName; }
+    bool set_app_package_name(const std::string& id);
+
+    const std::string& origin() const { return mCdmIdentifier.origin; }
+    bool set_origin(const std::string& id);
+
+   private:
+    WVDRM_DISALLOW_COPY_AND_ASSIGN(CdmIdentifierBuilder);
+
+    CdmIdentifier mCdmIdentifier;
+    bool mIsIdentifierSealed;
+
+    bool mUseSpoid;
+    std::string mDeviceId;
+    std::string mAppPackageName;
+
+    void calculateSpoid();
+  } mCdmIdentifierBuilder;
+
   sp<wvcdm::WvContentDecryptionModule> const mCDM;
-  CdmIdentifier mCdmIdentifier;
   WVGenericCryptoInterface* mCrypto;
   map<CdmSessionId, CryptoSession> mCryptoSessions;
   sp<IDrmPluginListener> mListener;
 
-  const std::string& appPackageName() const {
-     return mAppPackageName;
-   }
-
   status_t queryProperty(const std::string& property,
                          std::string& stringValue) const;