Use a direct include of strings headers in webkit/, part 2.

webkit/plugins/npapi/webplugin_delegate_impl.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 "webkit/plugins/npapi/webplugin_delegate_impl.h"
 
 #include <string>
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "base/process_util.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebInputEvent.h"
 #include "webkit/glue/webkit_glue.h"
 #include "webkit/plugins/npapi/plugin_instance.h"
 #include "webkit/plugins/npapi/plugin_lib.h"
 #include "webkit/plugins/npapi/plugin_stream_url.h"
 #include "webkit/plugins/npapi/plugin_utils.h"
 
 using WebKit::WebCursorInfo;
 using WebKit::WebInputEvent;
 
@@ skipping 273 matching lines @@
       resource_id, url, std::string(), notify_id);
 }
 
 WebPluginResourceClient* WebPluginDelegateImpl::CreateSeekableResourceClient(
     unsigned long resource_id, int range_request_id) {
   return instance()->GetRangeRequest(range_request_id);
 }
 
 }  // namespace npapi
 }  // namespace webkit