Use a direct include of strings headers in remoting/.

remoting/host/setup/start_host.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 <stdio.h>
 #include <termios.h>
 
 #include "base/at_exit.h"
 #include "base/command_line.h"
 #include "base/run_loop.h"
-#include "base/stringprintf.h"
+#include "base/strings/stringprintf.h"
 #include "base/threading/thread.h"
 #include "google_apis/gaia/gaia_urls.h"
 #include "net/url_request/url_fetcher.h"
 #include "net/url_request/url_request_context_getter.h"
 #include "remoting/host/service_urls.h"
 #include "remoting/host/setup/host_starter.h"
 #include "remoting/host/setup/oauth_helper.h"
 #include "remoting/host/setup/pin_validator.h"
 #include "remoting/host/url_request_context.h"
 
@@ skipping 155 matching lines @@
 
   // Destroy the HostStarter and URLRequestContextGetter before stopping the
   // IO thread.
   host_starter.reset();
   url_request_context_getter = NULL;
 
   io_thread.Stop();
 
   return g_started ? 0 : 1;
 }