[ObjC ARC] Converts ios/chrome/browser/ui/promos:unit_tests to ARC.

ios/chrome/browser/ui/promos/signin_promo_view_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 <UIKit/UIKit.h>
 
 #include <memory>
 
-#import "base/mac/scoped_nsobject.h"
 #include "base/memory/ptr_util.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/version.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "components/sync_preferences/pref_service_mock_factory.h"
 #include "components/sync_preferences/pref_service_syncable.h"
 #include "ios/chrome/browser/browser_state/test_chrome_browser_state.h"
 #include "ios/chrome/browser/prefs/browser_prefs.h"
 #include "ios/chrome/browser/signin/authentication_service_factory.h"
 #import "ios/chrome/browser/signin/authentication_service_fake.h"
 #import "ios/chrome/browser/ui/promos/signin_promo_view_controller.h"
 #include "ios/chrome/test/block_cleanup_test.h"
 #import "ios/public/provider/chrome/browser/signin/fake_chrome_identity_service.h"
 #include "ios/web/public/test/test_web_thread_bundle.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #import "third_party/ocmock/OCMock/OCMock.h"
 #import "third_party/ocmock/gtest_support.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 @interface SigninPromoViewController (ExposedForTesting)
 @property(nonatomic, readonly) UIView* accountsContainer;
 - (void)recordPromoDisplayed;
 + (base::Version)currentVersion;
 @end
 
 namespace {
 // Fake version used in tests.
 base::Version* gFakeCurrentVersion = nullptr;
 }
@@ skipping 26 matching lines @@
 
 enum ButtonTestingID {
   // IBUITag specified in the .xib file.
   FRONT_CLOSE_BUTTON_ID = 202,
 };
 
 class SigninPromoViewControllerTest : public BlockCleanupTest {
  public:
   ~SigninPromoViewControllerTest() override {}
 
-  SigninPromoViewController* controller() { return controller_.get(); }
+  SigninPromoViewController* controller() { return controller_; }
 
   void SetUp() override {
     BlockCleanupTest::SetUp();
     [FakeVersionSigninPromoViewController setFakeCurrentVersion:"1.0"];
     TestChromeBrowserState::Builder builder;
     builder.SetPrefService(CreatePrefService());
     builder.AddTestingFactory(
         AuthenticationServiceFactory::GetInstance(),
         AuthenticationServiceFake::CreateAuthenticationService);
     chrome_browser_state_ = builder.Build();
     ios::FakeChromeIdentityService::GetInstanceFromChromeProvider()
         ->AddIdentities(@[ @"foo", @"bar" ]);
-    controller_.reset([[FakeVersionSigninPromoViewController alloc]
-        initWithBrowserState:chrome_browser_state_.get()]);
+    controller_ = [[FakeVersionSigninPromoViewController alloc]
+        initWithBrowserState:chrome_browser_state_.get()];
   }
 
   void TearDown() override {
     NSUserDefaults* standardDefaults = [NSUserDefaults standardUserDefaults];
     [standardDefaults removeObjectForKey:kDisplayedSSORecallForMajorVersionKey];
     [standardDefaults synchronize];
     [FakeVersionSigninPromoViewController clearFakeCurrentVersion];
     BlockCleanupTest::TearDown();
   }
 
@@ skipping 11 matching lines @@
     SigninPromoViewController* signin_promo_view_controller =
         static_cast<SigninPromoViewController*>(controller());
     EXPECT_TRUE([signin_promo_view_controller
         isKindOfClass:[SigninPromoViewController class]]);
     [signin_promo_view_controller recordPromoDisplayed];
   }
 
  protected:
   web::TestWebThreadBundle thread_bundle_;
   std::unique_ptr<TestChromeBrowserState> chrome_browser_state_;
-  base::scoped_nsobject<SigninPromoViewController> controller_;
+  SigninPromoViewController* controller_;
 };
 
 TEST_F(SigninPromoViewControllerTest, TestConstructorDestructor) {
   EXPECT_TRUE(controller());
   EXPECT_TRUE([controller() view]);
 }
 
 TEST_F(SigninPromoViewControllerTest, TestWillDisplay) {
   EXPECT_TRUE([SigninPromoViewController
       shouldBePresentedForBrowserState:chrome_browser_state_.get()]);
@@ skipping 31 matching lines @@
 
 TEST_F(SigninPromoViewControllerTest, TestWillDisplayTwoMajorVersions) {
   SetPromoHasBeenShown();
   // Set the future version to be two major releases ahead.
   [FakeVersionSigninPromoViewController setFakeCurrentVersion:"3.0"];
   EXPECT_TRUE([FakeVersionSigninPromoViewController
       shouldBePresentedForBrowserState:chrome_browser_state_.get()]);
 }
 
 }  // namespace