Simplify registration of a test ChromeBrowserStateManager.

ios/chrome/browser/ui/settings/settings_navigation_controller_unittest.mm

 // Copyright 2013 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.
 
 #import "ios/chrome/browser/ui/settings/settings_navigation_controller.h"
 
 #import <Foundation/Foundation.h>
 
 #include <memory>
 
 #include "base/mac/scoped_nsautorelease_pool.h"
 #import "base/mac/scoped_nsobject.h"
 #include "base/memory/ptr_util.h"
 #include "components/search_engines/template_url_service.h"
 #include "ios/chrome/browser/browser_state/test_chrome_browser_state.h"
 #include "ios/chrome/browser/browser_state/test_chrome_browser_state_manager.h"
 #include "ios/chrome/browser/search_engines/template_url_service_factory.h"
 #import "ios/chrome/browser/signin/authentication_service.h"
 #include "ios/chrome/browser/signin/authentication_service_factory.h"
 #import "ios/chrome/browser/signin/authentication_service_fake.h"
 #include "ios/chrome/browser/sync/sync_setup_service.h"
 #include "ios/chrome/browser/sync/sync_setup_service_factory.h"
-#include "ios/chrome/test/testing_application_context.h"
+#include "ios/chrome/test/ios_chrome_scoped_testing_chrome_browser_state_manager.h"
 #include "ios/web/public/test/test_web_thread_bundle.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #import "testing/gtest_mac.h"
 #include "testing/platform_test.h"
 #import "third_party/ocmock/OCMock/OCMock.h"
 #include "third_party/ocmock/gtest_support.h"
 
 namespace {
 
 NSString* const kSpdyProxyEnabled = @"SpdyProxyEnabled";
 
 using testing::ReturnRef;
 
 class SettingsNavigationControllerTest : public PlatformTest {
  protected:
   SettingsNavigationControllerTest()
-      : browser_state_manager_(base::FilePath()) {}
-
-  void SetUp() override {
-    PlatformTest::SetUp();
-    TestingApplicationContext::GetGlobal()->SetChromeBrowserStateManager(
-        &browser_state_manager_);
-
+      : scoped_browser_state_manager_(
+            base::MakeUnique<TestChromeBrowserStateManager>(base::FilePath())) {
     TestChromeBrowserState::Builder test_cbs_builder;
     test_cbs_builder.AddTestingFactory(
         AuthenticationServiceFactory::GetInstance(),
         &AuthenticationServiceFake::CreateAuthenticationService);
     test_cbs_builder.AddTestingFactory(
         ios::TemplateURLServiceFactory::GetInstance(),
         ios::TemplateURLServiceFactory::GetDefaultFactory());
     chrome_browser_state_ = test_cbs_builder.Build();
 
     mockDelegate_.reset([[OCMockObject
         niceMockForProtocol:@protocol(SettingsNavigationControllerDelegate)]
         retain]);
 
     TemplateURLService* template_url_service =
         ios::TemplateURLServiceFactory::GetForBrowserState(
             chrome_browser_state_.get());
     template_url_service->Load();
 
     NSUserDefaults* defaults = [NSUserDefaults standardUserDefaults];
     initialValueForSpdyProxyEnabled_.reset(
         [[defaults stringForKey:kSpdyProxyEnabled] copy]);
     [defaults setObject:@"Disabled" forKey:kSpdyProxyEnabled];
   };
 
-  void TearDown() override {
+  ~SettingsNavigationControllerTest() override {
     if (initialValueForSpdyProxyEnabled_) {
       [[NSUserDefaults standardUserDefaults]
           setObject:initialValueForSpdyProxyEnabled_.get()
              forKey:kSpdyProxyEnabled];
     } else {
       [[NSUserDefaults standardUserDefaults]
           removeObjectForKey:kSpdyProxyEnabled];
     }
-    TestingApplicationContext::GetGlobal()->SetChromeBrowserStateManager(
-        nullptr);
-    PlatformTest::TearDown();
   }
 
-  web::TestWebThreadBundle threadBundle_;
-  TestChromeBrowserStateManager browser_state_manager_;
+  web::TestWebThreadBundle thread_bundle_;
+  IOSChromeScopedTestingChromeBrowserStateManager scoped_browser_state_manager_;
   std::unique_ptr<TestChromeBrowserState> chrome_browser_state_;
-  base::mac::ScopedNSAutoreleasePool pool;
+  base::mac::ScopedNSAutoreleasePool pool_;
   base::scoped_nsprotocol<id> mockDelegate_;
   base::scoped_nsobject<NSString> initialValueForSpdyProxyEnabled_;
 };
 
 // When navigation stack has more than one view controller,
 // -popViewControllerAnimated: successfully removes the top view controller.
 TEST_F(SettingsNavigationControllerTest, PopController) {
   base::scoped_nsobject<SettingsNavigationController> settingsController(
       [SettingsNavigationController
           newSettingsMainControllerWithMainBrowserState:chrome_browser_state_
@@ skipping 61 matching lines @@
                                     currentBrowserState:chrome_browser_state_
                                                             .get()
                                                delegate:mockDelegate_]);
   EXPECT_EQ(1U, [[settingsController viewControllers] count]);
   [[mockDelegate_ expect] closeSettings];
   [settingsController popViewControllerOrCloseSettingsAnimated:NO];
   EXPECT_OCMOCK_VERIFY(mockDelegate_);
 }
 
 }  // namespace