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

ios/chrome/browser/payments/js_payment_request_manager.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 "ios/chrome/browser/payments/js_payment_request_manager.h"
 
 #include "base/json/json_writer.h"
 #include "base/json/string_escape.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/values.h"
 #include "ios/web/public/payments/payment_request.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 
 // Sanitizes |JSON| and wraps it in quotes so it can be injected safely in
 // JavaScript.
 NSString* JSONEscape(NSString* JSON) {
   return base::SysUTF8ToNSString(
       base::GetQuotedJSONString(base::SysNSStringToUTF8(JSON)));
 }
 
 }  // namespace
@@ skipping 80 matching lines @@
 
 - (NSString*)scriptPath {
   return @"payment_request_manager";
 }
 
 - (NSString*)presenceBeacon {
   return @"__gCrWeb.paymentRequestManager";
 }
 
 @end