protected UniversalID resolveSourceArchiveID(DataType dataType) {
		if (dataType instanceof BuiltInDataType) {
			return DataTypeManager.BUILT_IN_ARCHIVE_UNIVERSAL_ID;
		}
		throw new IllegalArgumentException("Only Built-in data types can be resolved by the " +
			getClass().getSimpleName() + " manager.");
	}
Add the built in data types to the default built in folder if they
were not found in any other category.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/data/BuiltInDataTypeManager.java