Clean Up OEMCrypto Header

Merge from Widevine repo of http://go/wvgerrit/23482

Now that the documentation has been approved, it's time to
copy text from http://go/oemcrypto to OEMCryptoCENC.h

This also has all the little tweaks to the documents that have been
requested over the past couple of weeks.

b/31458046

Change-Id: I5b865031eb7945005c06bf1b00ecfaaedcad15f4

libwvdrmengine/cdm/core/include/oemcrypto_adapter.h

@@ -53,6 +53,23 @@ OEMCryptoResult OEMCrypto_CreateOldUsageEntry(SecurityLevel level,
     uint64_t time_since_last_decrypt, OEMCrypto_Usage_Entry_Status status,
     uint8_t* server_mac_key, uint8_t* client_mac_key, const uint8_t* pst,
     size_t pst_length);
+
+/* The following functions are deprecated in OEMCrypto v13.  They are defined
+ * here so that core cdm code may be backwards compatible with an OEMCrypto
+ * v12.
+ */
+extern "C" {
+OEMCryptoResult OEMCrypto_UpdateUsageTable();
+OEMCryptoResult OEMCrypto_DeactivateUsageEntry_12(const uint8_t* pst,
+                                                  size_t pst_length);
+OEMCryptoResult OEMCrypto_DeleteUsageEntry(
+    OEMCrypto_SESSION session, const uint8_t* pst, size_t pst_length,
+    const uint8_t* message, size_t message_length, const uint8_t* signature,
+    size_t signature_length);
+
+OEMCryptoResult OEMCrypto_ForceDeleteUsageEntry(const uint8_t* pst,
+                                                size_t pst_length);
+}  // extern "C"
 }  // namespace wvcdm
 
 #endif  // WVCDM_CORE_OEMCRYPTO_ADAPTER_H_