Replace deprecated base::NonThreadSafe in content/browser/appcache in favor of SequenceChecker.

content/browser/appcache/appcache_job.cc

 // Copyright (c) 2017 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 "content/browser/appcache/appcache_job.h"
 
 #include "base/command_line.h"
 #include "content/browser/appcache/appcache_request.h"
 #include "content/browser/appcache/appcache_url_loader_job.h"
 #include "content/browser/appcache/appcache_url_request_job.h"
@@ skipping 14 matching lines @@
           switches::kEnableNetworkService)) {
     job.reset(new AppCacheURLLoaderJob);
   } else {
     job.reset(new AppCacheURLRequestJob(request->GetURLRequest(),
                                         network_delegate, storage, host,
                                         is_main_resource, restart_callback));
   }
   return job;
 }
 
-AppCacheJob::~AppCacheJob() {}
+AppCacheJob::~AppCacheJob() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+}
 
 base::WeakPtr<AppCacheJob> AppCacheJob::GetWeakPtr() {
   return weak_factory_.GetWeakPtr();
 }
 
 net::URLRequestJob* AppCacheJob::AsURLRequestJob() {
   return nullptr;
 }
 
 AppCacheURLLoaderJob* AppCacheJob::AsURLLoaderJob() {
   return nullptr;
 }
 
 AppCacheJob::AppCacheJob() : weak_factory_(this) {}
 
 }  // namespace content