void addRootXML(String namespaceURI, String localName) {
        if (rootXML == null) {
            rootXML = new ArrayList<>();
        }
        rootXML.add(new RootXML(this, namespaceURI, localName));
    }
Add some rootXML info to this mime-type

@param namespaceURI
@param localName
tika-core/src/main/java/org/apache/tika/mime/MimeType.java