ScriptState::contextIsEmpty shouldn't return true for a context whose global object is detached

Source/bindings/core/v8/custom/V8WindowCustom.cpp

 /*
  * Copyright (C) 2009, 2011 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 316 matching lines @@
     m_scriptStateForDialogFrame = ScriptState::from(context);
 
     ScriptState::Scope scope(m_scriptStateForDialogFrame.get());
     m_scriptStateForDialogFrame->context()->Global()->Set(v8AtomicString(m_scriptState->isolate(), "dialogArguments"), m_dialogArguments);
 }
 
 v8::Handle<v8::Value> DialogHandler::returnValue() const
 {
     if (!m_scriptStateForDialogFrame)
         return v8Undefined();
-    ASSERT(!m_scriptStateForDialogFrame->contextIsEmpty());
+    ASSERT(!m_scriptStateForDialogFrame->contextIsValid());
 
     v8::Isolate* isolate = m_scriptStateForDialogFrame->isolate();
     v8::EscapableHandleScope handleScope(isolate);
     ScriptState::Scope scope(m_scriptStateForDialogFrame.get());
     v8::Local<v8::Value> returnValue = m_scriptStateForDialogFrame->context()->Global()->Get(v8AtomicString(isolate, "returnValue"));
     if (returnValue.IsEmpty())
         return v8Undefined();
     return handleScope.Escape(returnValue);
 }
 
@@ skipping 196 matching lines @@
     v8::Handle<v8::Context> context = toV8Context(frame, DOMWrapperWorld::current(isolate));
     if (context.IsEmpty())
         return v8Undefined();
 
     v8::Handle<v8::Object> global = context->Global();
     ASSERT(!global.IsEmpty());
     return global;
 }
 
 } // namespace blink