Add DEPS include rules so we don't accidentally use base

ppapi/tests/test_tcp_socket_private.cc

 // Copyright (c) 2011 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 "ppapi/tests/test_tcp_socket_private.h"
 
 #include <stdlib.h>
 
-#include "base/string_split.h"
 #include "ppapi/c/dev/ppb_url_util_dev.h"
 #include "ppapi/cpp/dev/url_util_dev.h"
 #include "ppapi/cpp/private/tcp_socket_private.h"
 #include "ppapi/cpp/var.h"
 #include "ppapi/tests/testing_instance.h"
 #include "ppapi/tests/test_utils.h"
 
 namespace {
 
 // Validates the first line of an HTTP response.
@@ skipping 189 matching lines @@
     if (rv < 0)
       return rv;
     if (rv == 0)
       return PP_ERROR_FAILED;
     written += rv;
   }
   if (written != s.size())
     return PP_ERROR_FAILED;
   return PP_OK;
 }