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

webkit/plugins/npapi/webplugin_delegate.h

 // Copyright (c) 2011 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.
 
 #ifndef WEBKIT_PLUGINS_NPAPI_WEBPLUGIN_DELEGATE_H_
 #define WEBKIT_PLUGINS_NPAPI_WEBPLUGIN_DELEGATE_H_
 
 #include <string>
 #include <vector>
 
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "build/build_config.h"
 #include "third_party/WebKit/public/platform/WebCanvas.h"
 #include "third_party/npapi/bindings/npapi.h"
 #include "ui/gfx/native_widget_types.h"
 #include "webkit/common/cursors/webcursor.h"
 #include "webkit/plugins/webkit_plugins_export.h"
 
 class GURL;
 struct NPObject;
 
@@ skipping 108 matching lines @@
   // Creates a WebPluginResourceClient instance for an existing stream that is
   // has become seekable.
   virtual WebPluginResourceClient* CreateSeekableResourceClient(
       unsigned long resource_id, int range_request_id) = 0;
 };
 
 }  // namespace npapi
 }  // namespace webkit
 
 #endif  // WEBKIT_PLUGINS_NPAPI_WEBPLUGIN_DELEGATE_H_