Implement simple http server with set cookie functionality.

ios/web/public/test/response_providers/html_response_provider_impl.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.
 
 #include "ios/web/public/test/response_providers/html_response_provider_impl.h"
 
 #include "ios/web/public/test/response_providers/response_provider.h"
 #include "net/http/http_response_headers.h"
 #include "net/http/http_status_code.h"
 #include "url/gurl.h"
@@ skipping 43 matching lines @@
   return HtmlResponseProviderImpl::Response(body, response_headers);
 }
 
 HtmlResponseProviderImpl::HtmlResponseProviderImpl(
     const std::map<GURL, std::string>& responses)
     : responses_(BuildResponseMap(
           responses,
           web::ResponseProvider::GetDefaultResponseHeaders())) {}
 
 HtmlResponseProviderImpl::HtmlResponseProviderImpl(
+    const std::map<GURL, std::string>& responses,
+    const std::string& cookie)
+    : responses_(BuildResponseMap(
+          responses,
+          web::ResponseProvider::GetDefaultResponseHeaders(cookie))) {}
+
+HtmlResponseProviderImpl::HtmlResponseProviderImpl(
     const std::map<GURL, HtmlResponseProviderImpl::Response>& responses)
     : responses_(responses) {}
 
 HtmlResponseProviderImpl::~HtmlResponseProviderImpl() {}
 
 bool HtmlResponseProviderImpl::CanHandleRequest(
     const web::ResponseProvider::Request& request) {
   return responses_.find(request.url) != responses_.end();
 }
 
 void HtmlResponseProviderImpl::GetResponseHeadersAndBody(
     const web::ResponseProvider::Request& request,
     scoped_refptr<net::HttpResponseHeaders>* headers,
     std::string* response_body) {
   const Response& response = responses_.at(request.url);
   *headers = response.headers;
   *response_body = response.body;
 }