Correctly track lifetime of promise rejection events

Source/bindings/core/v8/ScopedPersistent.h

 /*
  * Copyright (C) 2009 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 66 matching lines @@
     {
         m_handle.Reset(isolate, handle);
     }
 
     // Note: This is clear in the OwnPtr sense, not the v8::Handle sense.
     void clear()
     {
         m_handle.Reset();
     }
 
+    void setReference(const v8::Persistent<v8::Object>& parent, v8::Isolate* isolate)
+    {
+        isolate->SetReference(parent, m_handle);
+    }
+
     bool operator==(const ScopedPersistent<T>& other)
     {
         return m_handle == other.m_handle;
     }
 
     template <class S>
     bool operator==(const v8::Local<S> other) const
     {
         return m_handle == other;
     }
 
 private:
     // FIXME: This function does an unsafe handle access. Remove it.
     friend class V8AbstractEventListener;
     friend class V8PerIsolateData;
     ALWAYS_INLINE v8::Persistent<T>& getUnsafe()
     {
         return m_handle;
     }
 
     v8::Persistent<T> m_handle;
 };
 
 } // namespace blink
 
 #endif // ScopedPersistent_h