@Override
        public void apply() {
            new AcroFormDefaultsProcessor(document).process();
        }
Copied from AcroformDefaultFixup minus generation of appearances and handling of orphan
widgets, which we don't need.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-pdf-module/src/main/java/org/apache/tika/parser/pdf/PDFParser.java