ServiceWorker: Remove URLRequestJob::GetResponseCode implementations.

content/browser/service_worker/service_worker_write_to_cache_job.cc

Index: content/browser/service_worker/service_worker_write_to_cache_job.cc
diff --git a/content/browser/service_worker/service_worker_write_to_cache_job.cc b/content/browser/service_worker/service_worker_write_to_cache_job.cc
index efaf56c06ef4fb2a6ce757d7e07473fe1fd4cf61..add771446e73c633a31fafbd3d095c7e1224232f 100644
--- a/content/browser/service_worker/service_worker_write_to_cache_job.cc
+++ b/content/browser/service_worker/service_worker_write_to_cache_job.cc
@@ -162,12 +162,6 @@ void ServiceWorkerWriteToCacheJob::GetResponseInfo(
   *info = *http_info();
 }
 
-int ServiceWorkerWriteToCacheJob::GetResponseCode() const {
-  if (!http_info())
-    return -1;
-  return http_info()->headers->response_code();
-}
-
 void ServiceWorkerWriteToCacheJob::SetExtraRequestHeaders(
       const net::HttpRequestHeaders& headers) {
   std::string value;