[Sync] Create iOS factory for UserEventService.

ios/chrome/browser/sync/ios_user_event_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 "ios/chrome/browser/sync/ios_user_event_service_factory.h"
+
+#include <memory>
+#include <utility>
+
+#include "base/memory/ptr_util.h"
+#include "base/memory/singleton.h"
+#include "components/browser_sync/profile_sync_service.h"
+#include "components/keyed_service/ios/browser_state_dependency_manager.h"
+#include "components/sync/base/model_type.h"
+#include "components/sync/base/report_unrecoverable_error.h"
+#include "components/sync/user_events/no_op_user_event_service.h"
+#include "components/sync/user_events/user_event_service_impl.h"
+#include "components/sync/user_events/user_event_sync_bridge.h"
+#include "ios/chrome/browser/browser_state/browser_state_otr_helper.h"
+#include "ios/chrome/browser/browser_state/chrome_browser_state.h"
+#include "ios/chrome/browser/sync/ios_chrome_profile_sync_service_factory.h"
+#include "ios/chrome/common/channel_info.h"
+#include "ios/web/public/browser_state.h"
+
+// static
+syncer::UserEventService* IOSUserEventServiceFactory::GetForBrowserState(
+    ios::ChromeBrowserState* browser_state) {
+  return static_cast<syncer::UserEventService*>(
+      GetInstance()->GetServiceForBrowserState(browser_state, true));
+}
+
+// static
+IOSUserEventServiceFactory* IOSUserEventServiceFactory::GetInstance() {
+  return base::Singleton<IOSUserEventServiceFactory>::get();
+}
+
+IOSUserEventServiceFactory::IOSUserEventServiceFactory()
+    : BrowserStateKeyedServiceFactory(
+          "UserEventService",
+          BrowserStateDependencyManager::GetInstance()) {}
+
+IOSUserEventServiceFactory::~IOSUserEventServiceFactory() {}
+
+std::unique_ptr<KeyedService>
+IOSUserEventServiceFactory::BuildServiceInstanceFor(
+    web::BrowserState* browser_state) const {
+  if (browser_state->IsOffTheRecord()) {
+    return base::MakeUnique<syncer::NoOpUserEventService>();
+  }
+
+  syncer::ModelTypeStoreFactory store_factory =
+      browser_sync::ProfileSyncService::GetModelTypeStoreFactory(
+          syncer::USER_EVENTS, browser_state->GetStatePath());
+  syncer::ModelTypeSyncBridge::ChangeProcessorFactory processor_factory =
+      base::BindRepeating(&syncer::ModelTypeChangeProcessor::Create,
+                          base::BindRepeating(&syncer::ReportUnrecoverableError,
+                                              ::GetChannel()));
+  auto bridge = base::MakeUnique<syncer::UserEventSyncBridge>(
+      std::move(store_factory), std::move(processor_factory));
+  return base::MakeUnique<syncer::UserEventServiceImpl>(
+      IOSChromeProfileSyncServiceFactory::GetForBrowserState(
+          ios::ChromeBrowserState::FromBrowserState(browser_state)),
+      std::move(bridge));
+}
+
+web::BrowserState* IOSUserEventServiceFactory::GetBrowserStateToUse(
+    web::BrowserState* context) const {
+  return GetBrowserStateOwnInstanceInIncognito(context);
+}