Use Smart Lock preference instead of Chrome Password manager preference.

chrome/browser/password_manager/chrome_password_manager_client.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 "chrome/browser/password_manager/chrome_password_manager_client.h"
 
 #include <string>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 146 matching lines @@
   driver_factory_ =
       ContentPasswordManagerDriverFactory::FromWebContents(web_contents);
   log_manager_ = password_manager::LogManager::Create(
       password_manager::PasswordManagerInternalsServiceFactory::
           GetForBrowserContext(profile_),
       base::Bind(
           &ContentPasswordManagerDriverFactory::RequestSendLoggingAvailability,
           base::Unretained(driver_factory_)));
 
   saving_and_filling_passwords_enabled_.Init(
-      password_manager::prefs::kPasswordManagerSavingEnabled, GetPrefs());
+      password_manager::prefs::kCredentialsEnableService, GetPrefs());
   ReportMetrics(*saving_and_filling_passwords_enabled_, this, profile_);
   driver_factory_->RequestSendLoggingAvailability();
 }
 
 ChromePasswordManagerClient::~ChromePasswordManagerClient() {}
 
 bool ChromePasswordManagerClient::IsAutomaticPasswordSavingEnabled() const {
   return base::FeatureList::IsEnabled(
              password_manager::features::kEnableAutomaticPasswordSaving) &&
          chrome::GetChannel() == version_info::Channel::UNKNOWN;
@@ skipping 462 matching lines @@
       ChromePasswordManagerClient::FromWebContents(web_contents);
 
   // Try to bind to the driver, but if driver is not available for this render
   // frame host, the request will be just dropped. This will cause the message
   // pipe to be closed, which will raise a connection error on the peer side.
   if (!instance)
     return;
 
   instance->credential_manager_impl_.BindRequest(std::move(request));
 }