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

ios/chrome/browser/ui/activity_services/activity_type_util_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/activity_services/activity_type_util.h"
 
 #include "ios/chrome/browser/ui/activity_services/appex_constants.h"
 #include "ios/chrome/browser/ui/activity_services/print_activity.h"
 #include "ios/chrome/grit/ios_strings.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/gtest_mac.h"
 #include "ui/base/l10n/l10n_util_mac.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 
 void StringToTypeTestHelper(NSString* activityString,
                             activity_type_util::ActivityType expectedType) {
   EXPECT_EQ(activity_type_util::TypeFromString(activityString), expectedType);
 }
 
 TEST(ActivityTypeUtilTest, StringToTypeTest) {
   StringToTypeTestHelper(@"", activity_type_util::UNKNOWN);
   StringToTypeTestHelper(@"foo", activity_type_util::UNKNOWN);
@@ skipping 74 matching lines @@
                 @"com.dashlane.dashlanephonefinal.SafariExtension"));
   EXPECT_EQ(activity_services::kPasswordAppExVersionNumber,
             activity_type_util::PasswordAppExActivityVersion(
                 @"com.some-company.find-login-action.an-extension"));
   EXPECT_NE(activity_services::kPasswordAppExVersionNumber,
             activity_type_util::PasswordAppExActivityVersion(
                 @"com.apple.UIKit.activity.PostToFacebook"));
 }
 
 }  // namespace