@Override
	public UndefinedDBTraceData getPrimitiveAt(int offset) {
		if (offset < 0 || offset >= getLength()) {
			return null;
		}
		return this;
	}
Construct an undefined unit

@param trace the trace
@param snap the snap
@param address the address
@param thread the thread, if in a per-thread space
@param frameLevel the frame, if in a per-frame space
Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/database/listing/UndefinedDBTraceData.java