@Override
	void deleteMinimumVersion(String user) throws IOException {
		synchronized (fileSystem) {
			if (isVersioned) {
				deleteUser = user;
				versionedDb.deleteMinimumVersion();
			}
		}
	}
<code>LocalVersionedDbListener</code> provides a listener 
which maintains checkout and history data in response to 
VersionedDatabase callbacks.
Ghidra/Framework/FileSystem/src/main/java/ghidra/framework/store/local/LocalDatabaseItem.java