/usr/include/root/RooStats/HistFactory/ is in libroot-roofit-dev 5.34.00-2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/root/RooStats/HistFactory/Channel.h
/usr/include/root/RooStats/HistFactory/ConfigParser.h
/usr/include/root/RooStats/HistFactory/Data.h
/usr/include/root/RooStats/HistFactory/EstimateSummary.h
/usr/include/root/RooStats/HistFactory/FlexibleInterpVar.h
/usr/include/root/RooStats/HistFactory/HistFactoryException.h
/usr/include/root/RooStats/HistFactory/HistFactoryModelUtils.h
/usr/include/root/RooStats/HistFactory/HistFactorySimultaneous.h
/usr/include/root/RooStats/HistFactory/HistoToWorkspaceFactory.h
/usr/include/root/RooStats/HistFactory/HistoToWorkspaceFactoryFast.h
/usr/include/root/RooStats/HistFactory/LinInterpVar.h
/usr/include/root/RooStats/HistFactory/MakeModelAndMeasurementsFast.h
/usr/include/root/RooStats/HistFactory/Measurement.h
/usr/include/root/RooStats/HistFactory/ParamHistFunc.h
/usr/include/root/RooStats/HistFactory/PiecewiseInterpolation.h
/usr/include/root/RooStats/HistFactory/PreprocessFunction.h
/usr/include/root/RooStats/HistFactory/RooBarlowBeestonLL.h
/usr/include/root/RooStats/HistFactory/Sample.h
/usr/include/root/RooStats/HistFactory/Systematics.h