private List<VespaConfigChangeAction> validateDocumentTypeChanges() {
        return new DocumentTypeChangeValidator(id, currentDocType, nextDocType)
                       .validate();
    }
Validates the changes between a current and next document database that is part of an indexed search cluster.

@author geirst
config-model/src/main/java/com/yahoo/vespa/model/application/validation/change/search/DocumentDatabaseChangeValidator.java