binding: Changes the association among global-proxy/global/window-instance (2nd attempt).

third_party/WebKit/Source/bindings/core/v8/DOMWrapperMap.h

 /*
  * Copyright (C) 2012 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 62 matching lines @@
     if (UNLIKELY(ContainsKey(key))) {
       wrapper = NewLocal(isolate_, key);
       return false;
     }
     v8::Global<v8::Object> global(isolate_, wrapper);
     wrapper_type_info->ConfigureWrapper(&global);
     map_.Set(key, std::move(global));
     return true;
   }
 
+  void RemoveIfAny(KeyType* key) {
+    if (ContainsKey(key))
+      map_.Remove(key);
+  }
+
   void Clear() { map_.Clear(); }
 
   void RemoveAndDispose(KeyType* key) {
     DCHECK(ContainsKey(key));
     map_.Remove(key);
   }
 
   void MarkWrapper(KeyType* object) {
     map_.RegisterExternallyReferencedObject(object);
   }
@@ skipping 64 matching lines @@
     static void DisposeWeak(const v8::WeakCallbackInfo<WeakCallbackDataType>&);
   };
 
   v8::Isolate* isolate_;
   typename PersistentValueMapTraits::MapType map_;
 };
 
 }  // namespace blink
 
 #endif  // DOMWrapperMap_h