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

chrome/browser/automation/automation_event_observers.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 <string>
 
 #include "base/logging.h"
-#include "base/stringprintf.h"
+#include "base/strings/stringprintf.h"
 #include "chrome/browser/automation/automation_event_observers.h"
 #include "chrome/browser/automation/automation_event_queue.h"
 #include "chrome/browser/automation/automation_provider.h"
 #include "chrome/browser/automation/automation_provider_json.h"
 #include "content/public/browser/dom_operation_notification_details.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
 
 const char* DomEventObserver::kSubstringReplaceWithObserverId = "$(id)";
 
@@ skipping 77 matching lines @@
          event_name_.compare(dom_op_details->json) == 0)) {
       DictionaryValue* dict = new DictionaryValue;
       dict->SetString("type", "raised_event");
       dict->SetString("name", dom_op_details->json);
       NotifyEvent(dict);
     }
   }
   // Nothing should happen after RemoveIfDone() as it may delete the object.
   RemoveIfDone();
 }