Encrypt password values in LoginDatabase on Mac.

components/password_manager/core/browser/login_database_mac.cc

 // 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/password_manager/core/browser/login_database.h"
 
-// On the Mac, the LoginDatabase nulls out passwords, so that we can use the
-// rest of the database as a suplemental storage system to complement Keychain,
-// providing storage of fields Keychain doesn't allow.
+#include "components/os_crypt/os_crypt.h"
 
 namespace password_manager {
 
 // static
 LoginDatabase::EncryptionResult LoginDatabase::EncryptedString(
     const base::string16& plain_text,
     std::string* cipher_text) {
-  *cipher_text = std::string();
-  return ENCRYPTION_RESULT_SUCCESS;
+  // Handling the empty string shouldn't use the Keychain.

[vabr (Chromium), 2015/06/18 13:39:09]

It is not clear to me why it is important to mention not using Keychain here.
Also, the reference to the empty string might be unclear for readers without the
context of the changes in login_database.cc above.

[vasilii, 2015/06/18 14:28:14]

The comment is obsolete.

+  return OSCrypt::EncryptString16(plain_text, cipher_text)
+             ? ENCRYPTION_RESULT_SUCCESS
+             : ENCRYPTION_RESULT_SERVICE_FAILURE;
 }
 
 // static
 LoginDatabase::EncryptionResult LoginDatabase::DecryptedString(
     const std::string& cipher_text,
     base::string16* plain_text) {
-  *plain_text = base::string16();
-  return ENCRYPTION_RESULT_SUCCESS;
+  return OSCrypt::DecryptString16(cipher_text, plain_text)
+             ? ENCRYPTION_RESULT_SUCCESS
+             : ENCRYPTION_RESULT_SERVICE_FAILURE;
 }
 
 }  // namespace password_manager