Use a direct include of strings headers in chrome/browser/extensions/, part 4.

chrome/browser/extensions/window_open_apitest.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 "base/command_line.h"
 #include "base/memory/scoped_vector.h"
-#include "base/stringprintf.h"
+#include "base/strings/stringprintf.h"
 #include "chrome/browser/extensions/extension_apitest.h"
 #include "chrome/browser/extensions/extension_host.h"
 #include "chrome/browser/extensions/extension_process_manager.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/extension_test_message_listener.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_finder.h"
 #include "chrome/browser/ui/browser_iterator.h"
 #include "chrome/browser/ui/panels/panel_manager.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
@@ skipping 437 matching lines @@
       OpenWindow(browser()->tab_strip_model()->GetActiveWebContents(),
       GURL(std::string("chrome-extension://") + last_loaded_extension_id_ +
           "/newtab.html"), false, &newtab));
 
   // Extension API should succeed.
   bool result = false;
   ASSERT_TRUE(content::ExecuteScriptAndExtractBool(newtab, "testExtensionApi()",
                                                    &result));
   EXPECT_TRUE(result);
 }