1 files changed, 29 insertions, 1 deletions
diff --git a/WebCore/bridge/runtime.cpp b/WebCore/bridge/runtime.cpp
index 6934406..eac8586 100644
--- a/WebCore/bridge/runtime.cpp
+++ b/WebCore/bridge/runtime.cpp
@@ -48,12 +48,14 @@ Array::~Array()
 
 Instance::Instance(PassRefPtr<RootObject> rootObject)
     : _rootObject(rootObject)
+    , m_runtimeObject(0)
 {
     ASSERT(_rootObject);
 }
 
 Instance::~Instance()
 {
+    ASSERT(!m_runtimeObject);
 }
 
 static KJSDidExecuteFunctionPtr s_didExecuteFunction;
@@ -80,11 +82,37 @@ void Instance::end()
 
 RuntimeObjectImp* Instance::createRuntimeObject(ExecState* exec)
 {
+    ASSERT(_rootObject);
+    ASSERT(_rootObject->isValid());
+    if (m_runtimeObject)
+        return m_runtimeObject;
+    JSLock lock(SilenceAssertionsOnly);
+    m_runtimeObject = newRuntimeObject(exec);
+    _rootObject->addRuntimeObject(m_runtimeObject);
+    return m_runtimeObject;
+}
+
+RuntimeObjectImp* Instance::newRuntimeObject(ExecState* exec)
+{
     JSLock lock(SilenceAssertionsOnly);
-    
     return new (exec) RuntimeObjectImp(exec, this);
 }
 
+void Instance::willDestroyRuntimeObject()
+{
+    ASSERT(_rootObject);
+    ASSERT(_rootObject->isValid());
+    ASSERT(m_runtimeObject);
+    _rootObject->removeRuntimeObject(m_runtimeObject);
+    m_runtimeObject = 0;
+}
+
+void Instance::willInvalidateRuntimeObject()
+{
+    ASSERT(m_runtimeObject);
+    m_runtimeObject = 0;
+}
+
 RootObject* Instance::rootObject() const 
 { 
     return _rootObject && _rootObject->isValid() ? _rootObject.get() : 0;