More OEMCrypto Usage Table Unit Tests

Merge from widevine repo of http://go/wvgerrit/23421

This CL adds some more unit tests for big usage tables, and corrects a
problem found in the reference code.

Change-Id: Iae9a4406d79a13362223c2b4da7365b845d92382

libwvdrmengine/oemcrypto/test/oec_session_util.h

@@ -286,11 +286,12 @@ class Session {
   const vector<uint8_t>& encrypted_usage_entry() const {
     return encrypted_usage_entry_;
   }
-  // Generates a usage report for the specified pst.  If expect_success is true,
+  // Generates a usage report for the specified pst.  If there is success,
   // the report's signature is verified, and several fields are given sanity
   // checks.  If other is not null, then the mac keys are copied from other in
   // order to verify signatures.
-  void GenerateReport(const std::string& pst, bool expect_success = true,
+  void GenerateReport(const std::string& pst,
+                      OEMCryptoResult expected_result = OEMCrypto_SUCCESS,
                       Session* other = 0);
   // Move this usage entry to a new index.
   void MoveUsageEntry(uint32_t new_index, std::vector<uint8_t>* header_buffer,