in src/main/java/com/googlesource/gerrit/plugins/deleteproject/DeletePreconditions.java [173:178]
private void assertDeleteWithTags(Project.NameKey projectNameKey, boolean preserveGitRepository)
throws CannotDeleteProjectException {
if (!preserveGitRepository && !config.deletionWithTagsAllowed()) {
assertHasNoTags(projectNameKey);
}
}