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

ios/chrome/browser/ui/downloads/download_manager_controller_unittest.mm

 // Copyright 2014 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/downloads/download_manager_controller.h"
 
 #import <UIKit/UIKit.h>
 
 #include <memory>
 
-#import "base/mac/scoped_nsobject.h"
 #include "base/message_loop/message_loop.h"
 #import "ios/chrome/browser/store_kit/store_kit_launcher.h"
 #import "ios/chrome/browser/store_kit/store_kit_tab_helper.h"
 #import "ios/chrome/browser/web/chrome_web_test.h"
 #include "ios/web/public/test/test_web_thread.h"
 #include "net/base/net_errors.h"
 #include "net/http/http_response_headers.h"
 #include "net/url_request/test_url_fetcher_factory.h"
 #include "net/url_request/url_fetcher_delegate.h"
 #include "net/url_request/url_request_test_util.h"
 #include "testing/gtest_mac.h"
 #include "testing/platform_test.h"
 #import "third_party/ocmock/OCMock/OCMock.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 using net::HttpResponseHeaders;
 using net::URLRequestStatus;
 
 @interface DownloadManagerController (ExposedForTesting)
 - (UIView*)documentContainer;
 - (UIView*)progressBar;
 - (UIImageView*)documentIcon;
 - (UIImageView*)foldIcon;
 - (UILabel*)timeLeftLabel;
 - (UILabel*)fileTypeLabel;
@@ skipping 15 matching lines @@
 class DownloadManagerControllerTest : public ChromeWebTest {
  protected:
   void SetUp() override {
     ChromeWebTest::SetUp();
     _fetcher_factory.reset(new net::TestURLFetcherFactory());
     StoreKitTabHelper::CreateForWebState(web_state());
     StoreKitTabHelper* helper = StoreKitTabHelper::FromWebState(web_state());
     id mock_launcher =
         [OCMockObject niceMockForProtocol:@protocol(StoreKitLauncher)];
     helper->SetLauncher(mock_launcher);
-    _controller.reset([[DownloadManagerController alloc]
-        initWithWebState:web_state()
-             downloadURL:kTestURL]);
+    _controller =
+        [[DownloadManagerController alloc] initWithWebState:web_state()
+                                                downloadURL:kTestURL];
   }
-
   std::unique_ptr<net::TestURLFetcherFactory> _fetcher_factory;
-  base::scoped_nsobject<DownloadManagerController> _controller;
+  __strong DownloadManagerController* _controller;
 };
 
 TEST_F(DownloadManagerControllerTest, TestXibViewConnections) {
   EXPECT_TRUE([_controller documentContainer]);
   EXPECT_TRUE([_controller progressBar]);
   EXPECT_TRUE([_controller documentIcon]);
   EXPECT_TRUE([_controller foldIcon]);
   EXPECT_TRUE([_controller timeLeftLabel]);
   EXPECT_TRUE([_controller fileTypeLabel]);
   EXPECT_TRUE([_controller fileNameLabel]);
@@ skipping 51 matching lines @@
   EXPECT_FALSE(
       [[UIApplication sharedApplication] isNetworkActivityIndicatorVisible]);
 
   EXPECT_TRUE([_controller fileTypeLabel].hidden);
   EXPECT_FALSE([_controller downloadButton].hidden);
   EXPECT_FALSE([_controller errorIcon].hidden);
   EXPECT_FALSE([_controller errorOrSizeLabel].hidden);
 }
 
 }  // namespace