@Override
    public void process(boolean validate, boolean documentsOnly) {
        addDocumentFieldSet();
        addSearchFieldSet();
        // "Hook" the field sets on search onto the document types, since we will include them
        // on the document configs
        schema.getDocument().setFieldSets(schema.fieldSets());
    }
Adds field sets for 1) fields defined inside document type 2) fields inside search but outside document

@author Vegard Havdal
config-model/src/main/java/com/yahoo/schema/processing/BuiltInFieldSets.java