Merge changes I7cd424ae,I20f5d6a9

* changes:
  Add Duration Use Case integration tests
  Add some policy integration tests

libwvdrmengine/cdm/core/include/cdm_engine.h

@@ -347,11 +347,6 @@ class CdmEngine {
 
  protected:
   friend class CdmEngineFactory;
-  friend class ParallelCdmTest;
-  friend class WvCdmEnginePreProvTest;
-  friend class WvCdmTestBase;
-  friend class WvGenericCryptoTest;
-  friend class TestLicenseHolder;
 
   CdmEngine(FileSystem* file_system,
             std::shared_ptr<metrics::EngineMetrics> metrics);