Update the remaining include paths of base/string_piece.h to its new location.

chrome_frame/test/net/fake_external_tab.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_frame/test/net/fake_external_tab.h"
 
 #include <atlbase.h>
 #include <atlcom.h>
 #include <exdisp.h>
 #include <Winsock2.h>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/debugger.h"
 #include "base/file_util.h"
 #include "base/file_version_info.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/i18n/icu_util.h"
 #include "base/lazy_instance.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
 #include "base/prefs/json_pref_store.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service.h"
-#include "base/string_piece.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
+#include "base/strings/string_piece.h"
 #include "base/system_monitor/system_monitor.h"
 #include "base/test/test_timeouts.h"
 #include "base/threading/platform_thread.h"
 #include "base/threading/thread.h"
 #include "base/win/scoped_comptr.h"
 #include "base/win/scoped_handle.h"
 #include "chrome/app/chrome_main_delegate.h"
 #include "chrome/browser/automation/automation_provider_list.h"
 #include "chrome/browser/chrome_content_browser_client.h"
 #include "chrome/browser/prefs/browser_prefs.h"
@@ skipping 933 matching lines @@
   content::InitializeSandboxInfo(&sandbox_info);
   FakeMainDelegate delegate;
   content::ContentMain(
       reinterpret_cast<HINSTANCE>(GetModuleHandle(NULL)),
       &sandbox_info,
       &delegate);
 
   // Note:  In debug builds, we ExitProcess during PostDestroyThreads.
   return g_test_suite->test_result();
 }