Create TetherService, a TetherAllowed pref, and use DependencyManager for RegisterProfilePrefs call…

chrome/browser/chromeos/tether/tether_service_factory.cc

+// Copyright 2017 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/chromeos/tether/tether_service_factory.h"
+
+#include "base/memory/singleton.h"
+#include "chrome/browser/cryptauth/chrome_cryptauth_service_factory.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/common/pref_names.h"
+#include "components/keyed_service/content/browser_context_dependency_manager.h"
+#include "components/pref_registry/pref_registry_syncable.h"
+
+// static
+TetherServiceFactory* TetherServiceFactory::GetInstance() {
+  return base::Singleton<TetherServiceFactory>::get();
+}
+
+// static
+TetherService* TetherServiceFactory::GetForBrowserContext(
+    content::BrowserContext* browser_context) {
+  return static_cast<TetherService*>(
+      TetherServiceFactory::GetInstance()->GetServiceForBrowserContext(
+          browser_context, true));
+}
+
+TetherServiceFactory::TetherServiceFactory()
+    : BrowserContextKeyedServiceFactory(
+          "TetherService",
+          BrowserContextDependencyManager::GetInstance()) {
+  DependsOn(ChromeCryptAuthServiceFactory::GetInstance());
+}
+
+TetherServiceFactory::~TetherServiceFactory() {}
+
+KeyedService* TetherServiceFactory::BuildServiceInstanceFor(
+    content::BrowserContext* context) const {
+  return new TetherService(Profile::FromBrowserContext(context));
+}
+
+void TetherServiceFactory::RegisterProfilePrefs(
+    user_prefs::PrefRegistrySyncable* registry) {
+  TetherService::RegisterProfilePrefs(registry);
+}