Refine TwoHundredEntries tests

Merge from Widevine repo of http://go/wvgerrit/58440

This CL modifies the oemcrypto test TwoHundredEntries so that it
attempts to create more than 200 entries.  A device is allowed to fail
when such an attempt is made, but it must return an insufficient
resources error.

The test then verifies that each of the entries that were succesfully
created can be used to reload its license and the keys can be used for
decryption.

It then shrinks the usage table header, and verifies that the
remaining licenses can still be used for decryption.

bug: 112486006
test: unit tests (test code only)
Change-Id: I6e6edfb00f0553724e0f99fb4e5ea5c817450937

libwvdrmengine/oemcrypto/test/oec_session_util.h

@@ -290,7 +290,9 @@ class Session {
   // GenerateDerivedKeysFromSessionKey to install known encryption and mac keys.
   void InstallRSASessionTestKey(const vector<uint8_t>& wrapped_rsa_key);
   // Creates a new usage entry, and keeps track of the index.
-  void CreateNewUsageEntry();
+  // If status is null, we expect success, otherwise status is set to the
+  // return value.
+  void CreateNewUsageEntry(OEMCryptoResult *status = NULL);
   // Copy encrypted usage entry from other session, and then load it.
   // This session must already be open.
   void LoadUsageEntry(uint32_t index, const vector<uint8_t>& buffer);