[ObjC ARC] Converts ios/chrome/browser/web:eg_tests to ARC.

ios/chrome/browser/web/push_and_replace_state_navigation_egtest.mm

 // Copyright 2016 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 <XCTest/XCTest.h>
 
 #include "base/strings/sys_string_conversions.h"
 #include "components/strings/grit/components_strings.h"
 #include "ios/chrome/browser/ui/ui_util.h"
 #import "ios/chrome/test/earl_grey/chrome_earl_grey.h"
 #import "ios/chrome/test/earl_grey/chrome_earl_grey_ui.h"
 #import "ios/chrome/test/earl_grey/chrome_matchers.h"
 #import "ios/chrome/test/earl_grey/chrome_test_case.h"
 #import "ios/web/public/test/http_server.h"
 #include "ios/web/public/test/http_server_util.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 using chrome_test_util::BackButton;
 using chrome_test_util::ForwardButton;
 
 namespace {
 
 const char* kHistoryTestUrl =
     "http://ios/testing/data/http_server_files/history.html";
 const char* kNonPushedUrl =
     "http://ios/testing/data/http_server_files/pony.html";
 const char* kReplaceStateHashWithObjectURL =
@@ skipping 312 matching lines @@
                                      base::SysNSStringToUTF8(statusLabel))]
         assertWithMatcher:grey_notNil()];
   }
 
   [[EarlGrey selectElementWithMatcher:chrome_test_util::OmniboxText(
                                           urlToVerify.GetContent())]
       assertWithMatcher:grey_notNil()];
 }
 
 @end