[BrowserSwitcher] Add BrowserSwitcherService{,Factory}

BrowserSwitcherService is a per-BrowserContext class that manages
resources that should be shared between tabs in the same BrowserContext:
for now, the sitelist and browser launcher objects.

The BrowserSwitcherServiceFactory lets us easily create only one
BrowserSwitcherService per BrowserContext.

Bug: 876803
Change-Id: I6eb4c235143cfe38a077141b62e9332ed0f30a05
Reviewed-on: https://chromium-review.googlesource.com/1206698Reviewed-by: Julian Pastarmov <pastarmovj@chromium.org>
Commit-Queue: Nicolas Ouellet-Payeur <nicolaso@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589922}

chrome/browser/BUILD.gn

@@ -3148,6 +3148,10 @@ jumbo_split_static_library("browser") {
       "browser_switcher/alternative_browser_launcher.h",
       "browser_switcher/browser_switcher_prefs.cc",
       "browser_switcher/browser_switcher_prefs.h",
+      "browser_switcher/browser_switcher_service.cc",
+      "browser_switcher/browser_switcher_service.h",
+      "browser_switcher/browser_switcher_service_factory.cc",
+      "browser_switcher/browser_switcher_service_factory.h",
       "browser_switcher/browser_switcher_sitelist.cc",
       "browser_switcher/browser_switcher_sitelist.h",
       "downgrade/user_data_downgrade.cc",

chrome/browser/browser_switcher/browser_switcher_service.cc

+// Copyright 2018 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/browser_switcher/browser_switcher_service.h"
+
+#include "chrome/browser/browser_switcher/alternative_browser_launcher.h"
+#include "chrome/browser/browser_switcher/browser_switcher_sitelist.h"
+#include "chrome/browser/profiles/profile.h"
+#include "components/prefs/pref_service.h"
+#include "content/public/browser/browser_context.h"
+
+namespace browser_switcher {
+
+BrowserSwitcherService::BrowserSwitcherService(PrefService* prefs)
+    : launcher_(nullptr), sitelist_(nullptr), prefs_(prefs) {
+  DCHECK(prefs_);
+}
+
+BrowserSwitcherService::~BrowserSwitcherService() {}
+
+AlternativeBrowserLauncher* BrowserSwitcherService::launcher() {
+  if (!launcher_)
+    launcher_ = std::make_unique<AlternativeBrowserLauncher>(prefs_);
+  return launcher_.get();
+}
+
+BrowserSwitcherSitelist* BrowserSwitcherService::sitelist() {
+  if (!sitelist_)
+    sitelist_ = std::make_unique<BrowserSwitcherSitelist>(prefs_);
+  return sitelist_.get();
+}
+
+}  // namespace browser_switcher

chrome/browser/browser_switcher/browser_switcher_service.h

+// Copyright 2018 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_BROWSER_SWITCHER_BROWSER_SWITCHER_SERVICE_H_
+#define CHROME_BROWSER_BROWSER_SWITCHER_BROWSER_SWITCHER_SERVICE_H_
+
+#include "base/macros.h"
+#include "components/keyed_service/core/keyed_service.h"
+
+#include <memory>
+
+class PrefService;
+
+namespace browser_switcher {
+
+class AlternativeBrowserLauncher;
+class BrowserSwitcherSitelist;
+
+// Manages resources that can be accessed from a |BrowserSwitcherTabHelper|.
+class BrowserSwitcherService : public KeyedService {
+ public:
+  explicit BrowserSwitcherService(PrefService* prefs);
+  ~BrowserSwitcherService() override;
+
+  AlternativeBrowserLauncher* launcher();
+  BrowserSwitcherSitelist* sitelist();
+
+ private:
+  std::unique_ptr<AlternativeBrowserLauncher> launcher_;
+  std::unique_ptr<BrowserSwitcherSitelist> sitelist_;
+
+  PrefService* const prefs_;
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(BrowserSwitcherService);
+};
+
+}  // namespace browser_switcher
+
+#endif  // CHROME_BROWSER_BROWSER_SWITCHER_BROWSER_SWITCHER_SERVICE_H_

chrome/browser/browser_switcher/browser_switcher_service_factory.cc

+// Copyright 2018 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/browser_switcher/browser_switcher_service_factory.h"
+
+#include "chrome/browser/browser_switcher/browser_switcher_service.h"
+#include "chrome/browser/profiles/incognito_helpers.h"
+#include "chrome/browser/profiles/profile.h"
+#include "components/keyed_service/content/browser_context_dependency_manager.h"
+#include "components/keyed_service/core/keyed_service.h"
+#include "components/prefs/pref_service.h"
+#include "content/public/browser/browser_context.h"
+
+namespace browser_switcher {
+
+// static
+BrowserSwitcherServiceFactory* BrowserSwitcherServiceFactory::GetInstance() {
+  return base::Singleton<BrowserSwitcherServiceFactory>::get();
+}
+
+// static
+BrowserSwitcherService* BrowserSwitcherServiceFactory::GetForBrowserContext(
+    content::BrowserContext* browser_context) {
+  return static_cast<BrowserSwitcherService*>(
+      GetInstance()->GetServiceForBrowserContext(browser_context, true));
+}
+
+BrowserSwitcherServiceFactory::BrowserSwitcherServiceFactory()
+    : BrowserContextKeyedServiceFactory(
+          "BrowserSwitcherServiceFactory",
+          BrowserContextDependencyManager::GetInstance()) {}
+
+BrowserSwitcherServiceFactory::~BrowserSwitcherServiceFactory() {}
+
+KeyedService* BrowserSwitcherServiceFactory::BuildServiceInstanceFor(
+    content::BrowserContext* context) const {
+  return new BrowserSwitcherService(
+      Profile::FromBrowserContext(context)->GetPrefs());
+}
+
+content::BrowserContext* BrowserSwitcherServiceFactory::GetBrowserContextToUse(
+    content::BrowserContext* context) const {
+  // Use the original profile's BrowserSwitcherService, even in Incognito mode.
+  return chrome::GetBrowserContextRedirectedInIncognito(context);
+}
+
+}  // namespace browser_switcher

chrome/browser/browser_switcher/browser_switcher_service_factory.h

+// Copyright 2018 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_BROWSER_SWITCHER_BROWSER_SWITCHER_SERVICE_FACTORY_H_
+#define CHROME_BROWSER_BROWSER_SWITCHER_BROWSER_SWITCHER_SERVICE_FACTORY_H_
+
+#include "base/macros.h"
+#include "base/memory/singleton.h"
+#include "components/keyed_service/content/browser_context_keyed_service_factory.h"
+
+namespace content {
+class BrowserContext;
+}  // namespace content
+
+namespace browser_switcher {
+
+class BrowserSwitcherService;
+
+// Creates a |BrowserSwitcherService| for a BrowserContext.
+class BrowserSwitcherServiceFactory : public BrowserContextKeyedServiceFactory {
+ public:
+  static BrowserSwitcherServiceFactory* GetInstance();
+  static BrowserSwitcherService* GetForBrowserContext(
+      content::BrowserContext* browser_context);
+
+ private:
+  friend struct base::DefaultSingletonTraits<BrowserSwitcherServiceFactory>;
+
+  BrowserSwitcherServiceFactory();
+  ~BrowserSwitcherServiceFactory() override;
+
+  // BrowserContextKeyedServiceFactory overrides.
+  KeyedService* BuildServiceInstanceFor(
+      content::BrowserContext* context) const override;
+  content::BrowserContext* GetBrowserContextToUse(
+      content::BrowserContext* context) const override;
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserSwitcherServiceFactory);
+};
+
+}  // namespace browser_switcher
+
+#endif  // CHROME_BROWSER_BROWSER_SWITCHER_BROWSER_SWITCHER_SERVICE_FACTORY_H_