File util, generic crypto, and key query

This CL merges several CLs from the widevine repo:

http://go/wvgerrit/18012 Add support for querying allowed usage for key.
http://go/wvgerrit/17971 Add per-origin storage.
http://go/wvgerrit/18152 Add OEMCrypto's generic crypto operations to CDM.
http://go/wvgerrit/17911 QueryKeyControlInfo => QueryOemCryptoSessionId

Note: numbering in wv_cdm_types.h was added in this CL and will be
back ported to wvgerrit in a future CL.

Change-Id: Idb9e9a67e94f62f25dc16c5307f75a08b3430b64

libwvdrmengine/oemcrypto/mock/src/oemcrypto_engine_mock.cpp

@@ -1182,9 +1182,12 @@ bool SessionContext::IsUsageEntryValid() {
 
 void SessionContext::ReleaseUsageEntry() { usage_entry_ = NULL; }
 
-CryptoEngine::CryptoEngine()
-    : current_session_(NULL), use_test_keybox_(false),
-      usage_table_(new UsageTable(this)), rsa_key_(NULL) {
+CryptoEngine::CryptoEngine(wvcdm::FileSystem* file_system)
+    : current_session_(NULL),
+      use_test_keybox_(false),
+      file_system_(file_system),
+      usage_table_(new UsageTable(this)),
+      rsa_key_(NULL) {
   ERR_load_crypto_strings();
 
   if (!supports_keybox() && !LoadPkcs8RsaKey(kPrivateKey, kPrivateKeySize)) {