rv = ByteBufferImpl::Create(aOuter, nsIByteBuffer::GetIID(), (void**)&buf);
rv = ByteBufferImpl::Create(aOuter, NS_GET_IID(nsIByteBuffer), (void**)&buf);
NS_COM nsresult NS_NewByteBuffer(nsIByteBuffer** aInstancePtrResult,                                  nsISupports* aOuter,                                  PRUint32 aBufferSize){  nsresult rv;  nsIByteBuffer* buf;  rv = ByteBufferImpl::Create(aOuter, nsIByteBuffer::GetIID(), (void**)&buf);  if (NS_FAILED(rv)) return rv;      rv = buf->Init(aBufferSize);  if (NS_FAILED(rv)) {    NS_RELEASE(buf);    return rv;  }  *aInstancePtrResult = buf;  return rv;}