Replace further questionable HashMap::add usages in bindings

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 90 matching lines @@
         static Iterator End(Impl* impl) { return impl->end(); }
         static v8::PersistentContainerValue Value(Iterator& iter)
         {
             return iter->value;
         }
         static KeyType* Key(Iterator& iter) { return iter->key; }
         static v8::PersistentContainerValue Set(
             Impl* impl, KeyType* key, v8::PersistentContainerValue value)
         {
             v8::PersistentContainerValue oldValue = Get(impl, key);
-            impl->add(key, value);
+            impl->set(key, value);
             return oldValue;
         }
         static v8::PersistentContainerValue Get(const Impl* impl, KeyType* key)
         {
             return impl->get(key);
         }
 
         static v8::PersistentContainerValue Remove(Impl* impl, KeyType* key)
         {
             return impl->take(key);
@@ skipping 40 matching lines @@
     void* key)
 {
     ScriptForbiddenScope forbiddenScope;
     RELEASE_ASSERT(!value.IsEmpty()); // See crbug.com/368095.
     releaseObject(v8::Local<v8::Object>::New(isolate, value));
 }
 
 } // namespace blink
 
 #endif // DOMWrapperMap_h