Make //crypto factories return std::unique_ptr<>s

crypto/hmac_unittest.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stddef.h>
 
 #include <string>
 
 #include "base/macros.h"
 #include "crypto/hmac.h"
@@ skipping 269 matching lines @@
 }
 
 TEST(HMACTest, EmptyKey) {
   // Test vector from https://en.wikipedia.org/wiki/HMAC
   const char* kExpectedDigest =
       "\xFB\xDB\x1D\x1B\x18\xAA\x6C\x08\x32\x4B\x7D\x64\xB7\x1F\xB7\x63"
       "\x70\x69\x0E\x1D";
   base::StringPiece data("");
 
   crypto::HMAC hmac(crypto::HMAC::SHA1);
-  ASSERT_TRUE(hmac.Init(NULL, 0));
+  ASSERT_TRUE(hmac.Init(nullptr, 0));
 
   unsigned char digest[kSHA1DigestSize];
   EXPECT_TRUE(hmac.Sign(data, digest, kSHA1DigestSize));
   EXPECT_EQ(0, memcmp(kExpectedDigest, digest, kSHA1DigestSize));
 
   EXPECT_TRUE(hmac.Verify(
       data, base::StringPiece(kExpectedDigest, kSHA1DigestSize)));
 }