OEMCrypto Usage Tables

This CL adds usage tables to the OEMCrypto reference implementation
(mock) and unit tests.

There is also a new parameter called oem_crypto_require_usage_tables
that determines if the usage tables are required or not.  This is set
to true for Android and false for all other platforms.

This CL is most of OEMCrypto version 9 updates.

This CL is a copy of
https://widevine-internal-review.googlesource.com/#/c/9720
https://widevine-internal-review.googlesource.com/#/c/9874
https://widevine-internal-review.googlesource.com/#/c/9873

Change-Id: I78c4f7651306f9f79ba2260c3e04fb1eca7e20e3

libwvdrmengine/cdm/core/src/string_conversions.cpp

@@ -2,6 +2,7 @@
 
 #include "string_conversions.h"
 
+#include <arpa/inet.h>
 #include <ctype.h>
 #include <iostream>
 #include <stdio.h>
@@ -167,4 +168,21 @@ std::string UintToString(unsigned int value) {
   return out_string;
 }
 
+int64_t htonll64(int64_t x) {  // Convert to big endian (network-byte-order)
+  union {
+    uint32_t array[2];
+    int64_t number;
+  } mixed;
+  mixed.number = 1;
+  if (mixed.array[0] == 1) {
+    mixed.number = x;  // Little Endian.
+    uint32_t temp = mixed.array[0];
+    mixed.array[0] = htonl(mixed.array[1]);
+    mixed.array[1] = htonl(temp);
+    return mixed.number;
+  } else {
+    return x;  // Big Endian.
+  }
+}
+
 };  // namespace wvcdm