NS_IMETHOD AddObserver(nsIRDFObserver* n) { return mInner->AddObserver(n);
nsBookmarksService::AddObserver(nsIRDFObserver* aObserver) { if (! aObserver) return NS_ERROR_NULL_POINTER;  if (! mObservers.AppendObject(aObserver)) { return NS_ERROR_FAILURE;
    NS_IMETHOD AddObserver(nsIRDFObserver* n) {        return mInner->AddObserver(n);    }