Add more string_util functions to base namespace.

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/memory/ref_counted_memory.h"
 #include "base/strings/string_piece.h"
 #include "base/strings/string_util.h"
 #include "chrome/browser/search/instant_io_context.h"
@@ skipping 74 matching lines @@
     const content::URLDataSource::GotDataCallback& callback) {
   std::string origin;
   if (!GetOrigin(render_process_id, render_frame_id, &origin)) {
     callback.Run(NULL);
     return;
   }
 
   base::StringPiece template_js =
       ResourceBundle::GetSharedInstance().GetRawDataResource(resource_id);
   std::string response(template_js.as_string());
-  ReplaceFirstSubstringAfterOffset(&response, 0, "{{ORIGIN}}", origin);
+  base::ReplaceFirstSubstringAfterOffset(&response, 0, "{{ORIGIN}}", origin);
   callback.Run(base::RefCountedString::TakeString(&response));
 }