if (*aInputCharset)
if (!*aInputCharset || !nsCRT::strcasecmp("us-ascii", aInputCharset)) res = ccm2->GetCharsetAtom(NS_LITERAL_STRING("ISO-8859-1").get(), getter_AddRefs(charsetAtom)); else
MIME_get_unicode_decoder(const char* aInputCharset, nsIUnicodeDecoder **aDecoder){  nsresult res;  // get charset converters.  nsCOMPtr<nsICharsetConverterManager2> ccm2 =            do_GetService(NS_CHARSETCONVERTERMANAGER_CONTRACTID, &res);   if (NS_SUCCEEDED(res)) {    nsCOMPtr <nsIAtom> charsetAtom;    if (*aInputCharset)      res = ccm2->GetCharsetAtom(NS_ConvertASCIItoUCS2(aInputCharset).get(), getter_AddRefs(charsetAtom));    else      res = ccm2->GetCharsetAtom(NS_LITERAL_STRING("ISO-8859-1").get(), getter_AddRefs(charsetAtom));    // create a decoder (conv to unicode), ok if failed if we do auto detection    if (NS_SUCCEEDED(res))      res = ccm2->GetUnicodeDecoder(charsetAtom, aDecoder);  }     return res;}