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

Source/bindings/core/v8/custom/V8InjectedScriptManager.cpp

 /*
  * Copyright (C) 2012 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 100 matching lines @@
 
 bool InjectedScriptManager::canAccessInspectedWindow(ScriptState* scriptState)
 {
     ScriptState::Scope scope(scriptState);
     v8::Local<v8::Object> global = scriptState->context()->Global();
     if (global.IsEmpty())
         return false;
     v8::Handle<v8::Object> holder = V8Window::findInstanceInPrototypeChain(global, scriptState->isolate());
     if (holder.IsEmpty())
         return false;
-    LocalFrame* frame = V8Window::toImpl(holder)->frame();
+    LocalFrame* frame = toLocalDOMWindow(V8Window::toImpl(holder))->frame();

[dcheng, 2014/10/31 03:20:40]

For things like this, I assume that the browser will always route these requests
to the renderer hosting the frame. However, much of this browser-side routing
does not exist today, so I expect that we'll hit a bunch of asserts in
--site-per-process mode.

[haraken, 2014/10/31 06:07:04]

Don't we need to have:

  LocalDOMWindow* window = toLocalDOMWindow(V8Window::toImpl(holder));
  if (!window)
    return false;
  LocalFrame* frame = window->frame();

?

[dcheng, 2014/10/31 06:31:01]

The browser should be routing any calls of this nature correctly so we never end
up in the "wrong renderer": in other words, this should only be called in a
renderer where the frame is a LocalFrame. toLocalDOMWindow() will actually
RELEASE_ASSERT if the DOMWindow is of the wrong type. It's almost guaranteed
that this will assert right now. However, it only affects --site-per-process so
I'd prefer to make this as aggressive as possible so we can find problematic
areas. In the final state, there should be no checks for
isLocalDOMWindow()--since the browser will always route it to the renderer
hosting the frame, the DOMWindow will always be local.

 
     return BindingSecurity::shouldAllowAccessToFrame(scriptState->isolate(), frame, DoNotReportSecurityError);
 }
 
 void InjectedScriptManager::setWeakCallback(const v8::WeakCallbackData<v8::Object, InjectedScriptManager::CallbackData>& data)
 {
     InjectedScriptManager::CallbackData* callbackData = data.GetParameter();
     callbackData->injectedScriptManager->removeCallbackData(callbackData);
 }
 
 } // namespace blink