Move webpreferences.* from webkit/ to content/

chrome/browser/extensions/extension_webkit_preferences.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_WEBKIT_PREFERENCES_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_WEBKIT_PREFERENCES_H_
 
 #include "extensions/common/view_type.h"
 
+namespace content {
 struct WebPreferences;
+}
 
 namespace extensions {
 class Extension;
 }
 
 namespace extension_webkit_preferences {
 
 void SetPreferences(const extensions::Extension* extension,
                     extensions::ViewType render_view_type,
-                    WebPreferences* webkit_prefs);
+                    content::WebPreferences* webkit_prefs);
 
 }  // namespace extension_webkit_preferences
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_WEBKIT_PREFERENCES_H_