Use a direct include of strings headers in chrome/browser/r*-s*/.

chrome/browser/search/iframe_source.cc

 // Copyright 2013 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/search/iframe_source.h"
 
 #include "base/json/string_escape.h"
 #include "base/memory/ref_counted_memory.h"
-#include "base/string_util.h"
 #include "base/strings/string_piece.h"
+#include "base/strings/string_util.h"
 #include "chrome/browser/search/instant_io_context.h"
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "googleurl/src/gurl.h"
 #include "grit/browser_resources.h"
 #include "net/url_request/url_request.h"
 #include "ui/base/resource/resource_bundle.h"
 
 IframeSource::IframeSource() {
@@ skipping 67 matching lines @@
   }
 
   std::string js_escaped_origin;
   base::JsonDoubleQuote(origin, false, &js_escaped_origin);
   base::StringPiece template_js =
       ResourceBundle::GetSharedInstance().GetRawDataResource(resource_id);
   std::string response(template_js.as_string());
   ReplaceFirstSubstringAfterOffset(&response, 0, "{{ORIGIN}}", origin);
   callback.Run(base::RefCountedString::TakeString(&response));
 }