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

Source/modules/crypto/DOMWindowCrypto.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 40 matching lines @@
 DOMWindowCrypto& DOMWindowCrypto::from(LocalDOMWindow& window)
 {
     DOMWindowCrypto* supplement = static_cast<DOMWindowCrypto*>(WillBeHeapSupplement<LocalDOMWindow>::from(window, supplementName()));
     if (!supplement) {
         supplement = new DOMWindowCrypto(window);
         provideTo(window, supplementName(), adoptPtrWillBeNoop(supplement));
     }
     return *supplement;
 }
 
-Crypto* DOMWindowCrypto::crypto(LocalDOMWindow& window)
+Crypto* DOMWindowCrypto::crypto(DOMWindow& window)
 {
-    return DOMWindowCrypto::from(window).crypto();
+    return DOMWindowCrypto::from(toLocalDOMWindow(window)).crypto();
 }
 
 Crypto* DOMWindowCrypto::crypto() const
 {
     if (!m_crypto && frame())
         m_crypto = Crypto::create();
     return m_crypto.get();
 }
 
 void DOMWindowCrypto::trace(Visitor* visitor)
 {
     visitor->trace(m_crypto);
     WillBeHeapSupplement<LocalDOMWindow>::trace(visitor);
     DOMWindowProperty::trace(visitor);
 }
 
 } // namespace blink