Extract a DOMWindow interface from LocalDOMWindow and use it in the idl.

Source/core/html/HTMLFrameOwnerElement.h

 /*
  * Copyright (C) 2006, 2007, 2009 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
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 24 matching lines @@
 class Frame;
 class RenderPart;
 class Widget;
 
 class HTMLFrameOwnerElement : public HTMLElement, public FrameOwner {
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(HTMLFrameOwnerElement);
 public:
     virtual ~HTMLFrameOwnerElement();
 
     Frame* contentFrame() const { return m_contentFrame; }
-    LocalDOMWindow* contentWindow() const;
+    DOMWindow* contentWindow() const;
     Document* contentDocument() const;
 
     void setContentFrame(Frame&);
     void clearContentFrame();
 
     virtual void disconnectContentFrame();
 
     // Most subclasses use RenderPart (either RenderEmbeddedObject or RenderIFrame)
     // except for HTMLObjectElement and HTMLEmbedElement which may return any
     // RenderObject when using fallback content.
@@ skipping 74 matching lines @@
     static WillBeHeapHashCountedSet<RawPtrWillBeMember<Node>>& disabledSubtreeRoots();
 
     RawPtrWillBeMember<Node> m_root;
 };
 
 DEFINE_TYPE_CASTS(HTMLFrameOwnerElement, FrameOwner, owner, owner->isLocal(), owner.isLocal());
 
 } // namespace blink
 
 #endif // HTMLFrameOwnerElement_h