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

Source/bindings/core/v8/ScriptState.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "bindings/core/v8/ScriptState.h"
 
 #include "bindings/core/v8/V8Binding.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/frame/LocalFrame.h"
@@ skipping 14 matching lines @@
     data.GetValue()->SetAlignedPointerInEmbedderData(v8ContextPerContextDataIndex, 0);
     data.GetParameter()->clearContext();
     data.GetParameter()->deref();
 }
 
 ScriptState::ScriptState(v8::Handle<v8::Context> context, PassRefPtr<DOMWrapperWorld> world)
     : m_isolate(context->GetIsolate())
     , m_context(m_isolate, context)
     , m_world(world)
     , m_perContextData(V8PerContextData::create(context))
+    , m_globalObjectDetached(false)
 {
     ASSERT(m_world);
     m_context.setWeak(this, &weakCallback);
     context->SetAlignedPointerInEmbedderData(v8ContextPerContextDataIndex, this);
 }
 
 ScriptState::~ScriptState()
 {
     ASSERT(!m_perContextData);
     ASSERT(m_context.isEmpty());
 }
 
+void ScriptState::detachGlobalObject()
+{
+    ASSERT(!m_context.isEmpty());
+    context()->DetachGlobal();
+    m_globalObjectDetached = true;
+}
+
 bool ScriptState::evalEnabled() const
 {
     v8::HandleScope handleScope(m_isolate);
     return context()->IsCodeGenerationFromStringsAllowed();
 }
 
 void ScriptState::setEvalEnabled(bool enabled)
 {
     v8::HandleScope handleScope(m_isolate);
     return context()->AllowCodeGenerationFromStrings(enabled);
@@ skipping 48 matching lines @@
 {
     return m_executionContext;
 }
 
 void ScriptStateForTesting::setExecutionContext(ExecutionContext* executionContext)
 {
     m_executionContext = executionContext;
 }
 
 }