Use a direct include of strings headers in chrome/browser/ui/a*/.

chrome/browser/ui/app_list/search/search_controller.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/ui/app_list/search/search_controller.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/app_list/search/app_search_provider.h"
 #include "chrome/browser/ui/app_list/search/chrome_search_result.h"
 #include "chrome/browser/ui/app_list/search/history.h"
 #include "chrome/browser/ui/app_list/search/history_factory.h"
 #include "chrome/browser/ui/app_list/search/omnibox_provider.h"
 #include "chrome/browser/ui/app_list/search/search_provider.h"
 #include "chrome/browser/ui/app_list/search/webstore_provider.h"
 #include "content/public/browser/user_metrics.h"
@@ skipping 108 matching lines @@
   KnownResults known_results;
   if (history_ && history_->IsReady()) {
     history_->GetKnownResults(UTF16ToUTF8(search_box_->text()))
         ->swap(known_results);
   }
 
   mixer_->MixAndPublish(known_results);
 }
 
 }  // namespace app_list