Add ClosedTabCache Service and Factory

ClosedTabCache is a desktop feature to instantly restore closed tabs.

To own ClosedTabCache, this CL adds a KeyedService called
ClosedTabCacheService and a BrowserContextKeyedServiceFactory,
ClosedTabCacheServiceFactory, to retrieve the service.

ClosedTabCache design doc:
https://docs.google.com/document/d/1SF230MYWgroe4WikDMn82ETd3-HFRzylKtIk0HZRaOU/edit?usp=sharing

BUG=1100946

Change-Id: I397aa3abbebd9098694b20b9385fe75a7958c484
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2564966Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Sreeja Kamishetty <sreejakshetty@chromium.org>
Cr-Commit-Position: refs/heads/master@{#832708}

chrome/browser/BUILD.gn

@@ -3893,6 +3893,10 @@ static_library("browser") {
       "serial/serial_chooser_context_factory.cc",
       "serial/serial_chooser_context_factory.h",
       "serial/serial_chooser_histograms.h",
+      "sessions/closed_tab_cache_service.cc",
+      "sessions/closed_tab_cache_service.h",
+      "sessions/closed_tab_cache_service_factory.cc",
+      "sessions/closed_tab_cache_service_factory.h",
       "sharesheet/sharesheet_controller.h",
       "sharesheet/sharesheet_metrics.cc",
       "sharesheet/sharesheet_metrics.h",

chrome/browser/sessions/closed_tab_cache_service.cc

+// Copyright 2020 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/sessions/closed_tab_cache_service.h"
+
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/sessions/closed_tab_cache.h"
+
+ClosedTabCacheService::ClosedTabCacheService(Profile* profile)
+    : profile_(profile), cache_(std::make_unique<ClosedTabCache>()) {
+  // Incognito profiles don't allow tab restores.
+  DCHECK(!profile_->IsOffTheRecord());
+}
+
+ClosedTabCacheService::~ClosedTabCacheService() = default;
+
+void ClosedTabCacheService::Shutdown() {
+  cache_.reset();
+}
+
+ClosedTabCache& ClosedTabCacheService::closed_tab_cache() {
+  DCHECK(cache_);
+  return *cache_.get();
+}

chrome/browser/sessions/closed_tab_cache_service.h

+// Copyright 2020 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.
+
+#ifndef CHROME_BROWSER_SESSIONS_CLOSED_TAB_CACHE_SERVICE_H_
+#define CHROME_BROWSER_SESSIONS_CLOSED_TAB_CACHE_SERVICE_H_
+
+#include <memory>
+
+#include "components/keyed_service/core/keyed_service.h"
+
+class ClosedTabCache;
+class Profile;
+
+class ClosedTabCacheService : public KeyedService {
+ public:
+  explicit ClosedTabCacheService(Profile* profile);
+  ClosedTabCacheService(const ClosedTabCacheService&) = delete;
+  ClosedTabCacheService& operator=(const ClosedTabCacheService&) = delete;
+  ~ClosedTabCacheService() override;
+
+  ClosedTabCache& closed_tab_cache();
+
+  // KeyedService:
+  void Shutdown() override;
+
+ private:
+  Profile* profile_;
+
+  std::unique_ptr<ClosedTabCache> cache_;
+};
+
+#endif  // CHROME_BROWSER_SESSIONS_CLOSED_TAB_CACHE_SERVICE_H_

chrome/browser/sessions/closed_tab_cache_service_factory.cc

+// Copyright 2020 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/sessions/closed_tab_cache_service_factory.h"
+
+#include "build/build_config.h"
+#include "components/keyed_service/content/browser_context_dependency_manager.h"
+
+ClosedTabCacheServiceFactory::ClosedTabCacheServiceFactory()
+    : BrowserContextKeyedServiceFactory(
+          "ClosedTabCacheService",
+          BrowserContextDependencyManager::GetInstance()) {}
+
+// static
+ClosedTabCacheService* ClosedTabCacheServiceFactory::GetForProfile(
+    Profile* profile) {
+  return static_cast<ClosedTabCacheService*>(
+      GetInstance()->GetServiceForBrowserContext(profile, true));
+}
+
+ClosedTabCacheServiceFactory* ClosedTabCacheServiceFactory::GetInstance() {
+  return base::Singleton<ClosedTabCacheServiceFactory>::get();
+}
+
+KeyedService* ClosedTabCacheServiceFactory::BuildServiceInstanceFor(
+    content::BrowserContext* context) const {
+  if (context->IsOffTheRecord())
+    return nullptr;
+  return new ClosedTabCacheService(static_cast<Profile*>(context));
+}
+
+bool ClosedTabCacheServiceFactory::ServiceIsCreatedWithBrowserContext() const {
+  return true;
+}

chrome/browser/sessions/closed_tab_cache_service_factory.h

+// Copyright 2020 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.
+
+#ifndef CHROME_BROWSER_SESSIONS_CLOSED_TAB_CACHE_SERVICE_FACTORY_H_
+#define CHROME_BROWSER_SESSIONS_CLOSED_TAB_CACHE_SERVICE_FACTORY_H_
+
+#include "base/memory/singleton.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/sessions/closed_tab_cache_service.h"
+#include "components/keyed_service/content/browser_context_keyed_service_factory.h"
+
+class ClosedTabCacheServiceFactory : public BrowserContextKeyedServiceFactory {
+ public:
+  // Returns the ClosedTabCacheService for |profile|.
+  static ClosedTabCacheService* GetForProfile(Profile* profile);
+
+  static ClosedTabCacheServiceFactory* GetInstance();
+
+ private:
+  friend struct base::DefaultSingletonTraits<ClosedTabCacheServiceFactory>;
+
+  ClosedTabCacheServiceFactory();
+  ~ClosedTabCacheServiceFactory() override = default;
+
+  // BrowserContextKeyedServiceFactory:
+  KeyedService* BuildServiceInstanceFor(
+      content::BrowserContext* context) const override;
+  bool ServiceIsCreatedWithBrowserContext() const override;
+};
+
+#endif  // CHROME_BROWSER_SESSIONS_CLOSED_TAB_CACHE_SERVICE_FACTORY_H_