[chromium-style] out-of-line default constructors and destructors

atom/browser/net/url_request_string_job.cc

@@ -15,6 +15,8 @@ URLRequestStringJob::URLRequestStringJob(net::URLRequest* request,
                                          net::NetworkDelegate* network_delegate)
     : JsAsker<net::URLRequestSimpleJob>(request, network_delegate) {}
 
+URLRequestStringJob::~URLRequestStringJob() = default;
+
 void URLRequestStringJob::StartAsync(std::unique_ptr<base::Value> options) {
   if (options->IsType(base::Value::Type::DICTIONARY)) {
     base::DictionaryValue* dict =