Reland: Reland: Implement new Blink IDL attribute [SetReference]

Source/bindings/v8/DOMWrapperMap.h

Index: Source/bindings/v8/DOMWrapperMap.h
diff --git a/Source/bindings/v8/DOMWrapperMap.h b/Source/bindings/v8/DOMWrapperMap.h
index 53d0206f319919a6b51d2f803837dcb781d1546b..469450089e3fc9c5ee3aba3c40725d63786808f1 100644
--- a/Source/bindings/v8/DOMWrapperMap.h
+++ b/Source/bindings/v8/DOMWrapperMap.h
@@ -63,6 +63,11 @@ public:
         return true;
     }
 
+    void setReference(const v8::Persistent<v8::Object>& parent, KeyType* key, v8::Isolate* isolate)
+    {
+        m_map.get(key).setReferenceFrom(parent, isolate);
+    }
+
     bool containsKey(KeyType* key)
     {
         return m_map.find(key) != m_map.end();