DevTools: remove the --remote-debugging-frontend flag.

chrome/browser/devtools/remote_debugging_server.cc

 // Copyright (c) 2012 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 "chrome/browser/devtools/remote_debugging_server.h"
 
 #include "chrome/browser/devtools/browser_list_tabcontents_provider.h"
 #include "chrome/browser/ui/webui/devtools_ui.h"
 #include "content/public/browser/devtools_http_handler.h"
 #include "net/socket/tcp_listen_socket.h"
 
 RemoteDebuggingServer::RemoteDebuggingServer(
     chrome::HostDesktopType host_desktop_type,
     const std::string& ip,
-    int port,
-    const std::string& frontend_url) {
+    int port) {
   devtools_http_handler_ = content::DevToolsHttpHandler::Start(
       new net::TCPListenSocketFactory(ip, port),
-      frontend_url,
+      "",
       new BrowserListTabContentsProvider(host_desktop_type));
 }
 
 RemoteDebuggingServer::~RemoteDebuggingServer() {
   devtools_http_handler_->Stop();
 }