Refactor oemcrypto mock into stand alone reference code

Merge from Widevine repo of http://go/wvgerrit/46204
Refactor utility code - split the mock, step 1

Merge from Widevine repo of http://go/wvgerrit/46205
Move some OEMCrypto types to common header - split the mock, step 2

Merge from Widevine repo of http://go/wvgerrit/46206
Split mock into two -- step 3

Merge from Widevine repo of http://go/wvgerrit/47460
Split the mock into two -- step 3.5

The CL moves several files used by oemcrypto and cdm into a common
subdirectory, so that it may more easily be shared with partners.

The CORE_DISALLOW_COPY_AND_ASSIGN macro was moved to its own header in
the util/include directory.

This CL removes some references to the mock from other code, and puts
some constants and types, such as the definition of the keybox, into a
header in oemcrypto.

Test: tested as part of http://go/ag/4674759
bug: 76393338
Change-Id: I75b4bde7062ed8ee572c97ebc2f4da018f4be0c9

libwvdrmengine/cdm/util/include/string_conversions.h

@@ -0,0 +1,30 @@
+// Copyright 2013 Google Inc. All Rights Reserved.
+
+#ifndef WVCDM_UTIL_STRING_CONVERSIONS_H_
+#define WVCDM_UTIL_STRING_CONVERSIONS_H_
+
+#include <stddef.h>
+#include <stdint.h>
+#include <string>
+#include <vector>
+
+namespace wvcdm {
+
+std::vector<uint8_t> a2b_hex(const std::string& b);
+std::vector<uint8_t> a2b_hex(const std::string& label, const std::string& b);
+std::string a2bs_hex(const std::string& b);
+std::string b2a_hex(const std::vector<uint8_t>& b);
+std::string b2a_hex(const std::string& b);
+std::string Base64Encode(const std::vector<uint8_t>& bin_input);
+std::vector<uint8_t> Base64Decode(const std::string& bin_input);
+std::string Base64SafeEncode(const std::vector<uint8_t>& bin_input);
+std::string Base64SafeEncodeNoPad(const std::vector<uint8_t>& bin_input);
+std::vector<uint8_t> Base64SafeDecode(const std::string& bin_input);
+std::string HexEncode(const uint8_t* bytes, unsigned size);
+std::string IntToString(int value);
+int64_t htonll64(int64_t x);
+inline int64_t ntohll64(int64_t x) { return htonll64(x); }
+
+}  // namespace wvcdm
+
+#endif  // WVCDM_UTIL_STRING_CONVERSIONS_H_