Add unit test for fdrm's MD5

core/fdrm/crypto/fx_crypt.h

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #ifndef CORE_FDRM_CRYPTO_FX_CRYPT_H_
 #define CORE_FDRM_CRYPTO_FX_CRYPT_H_
 
 #include "core/fxcrt/fx_system.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
+struct CRYPT_md5_context {
+  uint32_t total[2];
+  uint32_t state[4];
+  uint8_t buffer[64];
+};
+
 void CRYPT_ArcFourCryptBlock(uint8_t* data,
                              uint32_t size,
                              const uint8_t* key,
                              uint32_t keylen);
 void CRYPT_ArcFourSetup(void* context, const uint8_t* key, uint32_t length);
 void CRYPT_ArcFourCrypt(void* context, uint8_t* data, uint32_t size);
 void CRYPT_AESSetKey(void* context,
                      uint32_t blocklen,
                      const uint8_t* key,
                      uint32_t keylen,
@@ skipping 36 matching lines @@
 void CRYPT_SetPubKeyDecryptor(bool (*func)(const uint8_t* pData,
                                            uint32_t size,
                                            uint8_t* data_buf,
                                            uint32_t& data_len));
 
 #ifdef __cplusplus
 };
 #endif
 
 #endif  // CORE_FDRM_CRYPTO_FX_CRYPT_H_