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

components/os_crypt/os_crypt_mac.mm

 // Copyright 2014 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 "components/os_crypt/os_crypt.h"
 
 #include <CommonCrypto/CommonCryptor.h>  // for kCCBlockSizeAES128
 #include <stddef.h>
 
 #include "base/command_line.h"
@@ skipping 59 matching lines @@
   // returning.
   key_is_cached = true;
 
   if (password.empty())
     return cached_encryption_key;
 
   std::string salt(kSalt);
 
   // Create an encryption key from our password and salt. The key is
   // intentionally leaked.
-  cached_encryption_key =
-      crypto::SymmetricKey::DeriveKeyFromPassword(crypto::SymmetricKey::AES,
-                                                  password,
-                                                  salt,
-                                                  kEncryptionIterations,
-                                                  kDerivedKeySizeInBits);
+  cached_encryption_key = crypto::SymmetricKey::DeriveKeyFromPassword(
+                              crypto::SymmetricKey::AES, password, salt,
+                              kEncryptionIterations, kDerivedKeySizeInBits)
+                              .release();
   ANNOTATE_LEAKING_OBJECT_PTR(cached_encryption_key);
   DCHECK(cached_encryption_key);
   return cached_encryption_key;
 }
 
 }  // namespace
 
 bool OSCrypt::EncryptString16(const base::string16& plaintext,
                               std::string* ciphertext) {
   return EncryptString(base::UTF16ToUTF8(plaintext), ciphertext);
@@ skipping 66 matching lines @@
   if (!encryptor.Decrypt(raw_ciphertext, plaintext))
     return false;
 
   return true;
 }
 
 void OSCrypt::UseMockKeychain(bool use_mock) {
   use_mock_keychain = use_mock;
 }