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

ios/chrome/browser/passwords/password_controller_off_the_record_unittest.mm

 // Copyright 2015 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 <memory>
 
-#import "base/mac/scoped_nsobject.h"
 #include "base/memory/ptr_util.h"
 #include "components/password_manager/core/browser/stub_password_manager_client.h"
 #include "ios/chrome/browser/browser_state/test_chrome_browser_state.h"
 #import "ios/chrome/browser/passwords/password_controller.h"
 #import "ios/web/public/test/test_web_state.h"
 #import "ios/web/public/test/web_test_with_web_state.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 
 class IncognitoPasswordManagerClient
     : public password_manager::StubPasswordManagerClient {
  public:
   bool IsOffTheRecord() const override { return true; }
 };
 
 }  // namespace
 
 class OffTheRecordWebState : public web::TestWebState {
  public:
   OffTheRecordWebState() {
     TestChromeBrowserState::Builder test_cbs_builder;
     chrome_browser_state_ = test_cbs_builder.Build();
   }
 
   web::BrowserState* GetBrowserState() const override {
     return chrome_browser_state_->GetOffTheRecordChromeBrowserState();
   }
 
  private:
   std::unique_ptr<TestChromeBrowserState> chrome_browser_state_;
 };
 
 class PasswordControllerOffTheRecordTest : public web::WebTestWithWebState {
  public:
   void SetUp() override {
     web::WebTestWithWebState::SetUp();
-    password_controller_.reset([[PasswordController alloc]
+    password_controller_ = [[PasswordController alloc]
            initWithWebState:&off_the_record_web_state_
         passwordsUiDelegate:nil
-                     client:base::MakeUnique<
-                                IncognitoPasswordManagerClient>()]);
+                     client:base::MakeUnique<IncognitoPasswordManagerClient>()];
   }
 
   void TearDown() override {
     [password_controller_ detach];
     web::WebTestWithWebState::TearDown();
   }
 
  protected:
   OffTheRecordWebState off_the_record_web_state_;
-  base::scoped_nsobject<PasswordController> password_controller_;
+  PasswordController* password_controller_;
 };
 
 // Check that if the PasswordController is told (by the PasswordManagerClient)
 // that this is Incognito, it won't enable password generation.
 TEST_F(PasswordControllerOffTheRecordTest, PasswordGenerationDisabled) {
   EXPECT_FALSE([this->password_controller_ passwordGenerationManager]);
 }