Implemented ext.contextMenus for Safari

safari/content.js

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2013 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 295 matching lines @@
 
   ext.onMessage = new MessageEventTarget(safari.self);
 
   // Safari does not pass the element which the context menu is refering to
   // so we need to add it to the event's user info.
   document.addEventListener("contextmenu", function(event)
   {
     var element = event.srcElement;
     safari.self.tab.setContextMenuEventUserInfo(event, {
       srcUrl: ("src" in element) ? element.src : null,
-      tagName: element.tagName
+      tagName: element.localName
     });
   }, false);
 })();