anchor.diff:        } else {
           throw new HttpException("Unexpected type for header named $name");
         }
  -    } else if (name.toLowerCase() == "expires") {
  +    } else if (lowerCaseName == "expires") {
         if (value is Date) {
           expires = value;
         } else if (value is String) {
  
positive.code:         }
          _set("host", value);
        }
      } else if (name.toLowerCase() == "content-type") {
        _set("content-type", value);
      } else {
        name = name.toLowerCase();
        List<String> values = _headers[name];
        if (values == null) {
          values = new List<String>();
  
negative.code:       } else {
          throw new HttpException("Unexpected type for header named $name");
        }
      } else if (lowerCaseName == "host") {
        int pos = value.indexOf(":");
        if (pos == -1) {
          _host = value;
  