Implement languagechange event, fired when accept languages changes.

Source/core/html/HTMLFrameSetElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Simon Hausmann (hausmann@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2006, 2009, 2010 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 127 matching lines @@
     else if (name == onscrollAttr)
         document().setWindowAttributeEventListener(EventTypeNames::scroll, createAttributeEventListener(document().frame(), name, value));
     else if (name == onstorageAttr)
         document().setWindowAttributeEventListener(EventTypeNames::storage, createAttributeEventListener(document().frame(), name, value));
     else if (name == ononlineAttr)
         document().setWindowAttributeEventListener(EventTypeNames::online, createAttributeEventListener(document().frame(), name, value));
     else if (name == onofflineAttr)
         document().setWindowAttributeEventListener(EventTypeNames::offline, createAttributeEventListener(document().frame(), name, value));
     else if (name == onpopstateAttr)
         document().setWindowAttributeEventListener(EventTypeNames::popstate, createAttributeEventListener(document().frame(), name, value));
+    else if (name == onlanguagechangeAttr)
+        document().setWindowAttributeEventListener(EventTypeNames::languagechange, createAttributeEventListener(document().frame(), name, value));
     else
         HTMLElement::parseAttribute(name, value);
 }
 
 bool HTMLFrameSetElement::rendererIsNeeded(const RenderStyle& style)
 {
     // For compatibility, frames render even when display: none is set.
     // However, we delay creating a renderer until stylesheets have loaded.
     return style.isStyleAvailable();
 }
@@ skipping 59 matching lines @@
     Element* frameElement = children()->namedItem(name);
     if (!isHTMLFrameElement(frameElement))
         return 0;
     Document* document = toHTMLFrameElement(frameElement)->contentDocument();
     if (!document || !document->frame())
         return 0;
     return document->domWindow();
 }
 
 } // namespace WebCore