Merge of usage reporting and license changes from WV CDM repo

* CdmSession unittest and license request time changes
  b/15914199
  Merge of https://widevine-internal-review.googlesource.com/#/c/10597/

* Specify OEMCrypto API version in client capabilities
  b/15388863
  Merge of https://widevine-internal-review.googlesource.com/#/c/10616/

* Report start and last play time in license request
  b/15995227
  Merge of https://widevine-internal-review.googlesource.com/#/c/10617/

* Respect can_play flag
  b/15330338
  Merge of https://widevine-internal-review.googlesource.com/#/c/10619/

* Restore offline session information
  b/16009274
  Merge of https://widevine-internal-review.googlesource.com/#/c/10641/

Change-Id: I17fdc309efbc1d44385a86a368df11b1349b29c2

libwvdrmengine/cdm/core/include/properties.h

@@ -87,6 +87,14 @@ class Properties {
     security_level_path_backward_compatibility_support_ = flag;
   }
 
+#if defined(UNIT_TEST)
+  FRIEND_TEST(CdmSessionTest, InitWithCertificate);
+  FRIEND_TEST(CdmSessionTest, InitWithKeybox);
+  FRIEND_TEST(CdmSessionTest, ReInitFail);
+  FRIEND_TEST(CdmSessionTest, InitFailCryptoError);
+  FRIEND_TEST(CdmSessionTest, InitNeedsProvisioning);
+#endif
+
  private:
   static bool oem_crypto_use_secure_buffers_;
   static bool oem_crypto_use_fifo_;