@Override
	public synchronized void clearUndo(boolean isCheckedOut) {
		if (inTransaction) {
			throw new IllegalStateException("Cannot clear in a transaction");
		}

		if (!isCheckedOut) { // if not versioned, wipe out change sets
			clearAll();
		}

		clearUndo();
	}
Construct a new ProgramChangeSet.
@param addrMap the address map.
@param numUndos the number of undo change sets to track.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/ProgramDBChangeSet.java