Headless: Pass devtools request id to the URLFetcher

headless/public/util/http_url_fetcher.cc

Index: headless/public/util/http_url_fetcher.cc
diff --git a/headless/public/util/http_url_fetcher.cc b/headless/public/util/http_url_fetcher.cc
index af5451218dd7e366c0add8348d4460dd190ed8ca..a3171b3f02e5fbb9b72c4ed0cd5c360a6dbd20fa 100644
--- a/headless/public/util/http_url_fetcher.cc
+++ b/headless/public/util/http_url_fetcher.cc
@@ -184,6 +184,7 @@ HttpURLFetcher::~HttpURLFetcher() {}
 void HttpURLFetcher::StartFetch(const GURL& rewritten_url,
                                 const std::string& method,
                                 const net::HttpRequestHeaders& request_headers,
+                                const std::string& devtools_request_id,
                                 ResultListener* result_listener) {
   delegate_.reset(new Delegate(rewritten_url, method, request_headers,
                                url_request_context_, result_listener));