RootCore/Packages.h Removals, 21.2 branch (2020.11.13.)

This is meant to fix the issue described in ATLASG-1571.

While AnalysisBase-21.2 still generates a RootCore/Packages.h file just to make it a little easier to build some terribly old analysis codebases, it is not set up to be used in the public interface of a class that has a dictionary generated for it. As ROOT is not made aware at runtime where to find this header.

Instead of adding the header (back) to the environment setup, I rather just removed the only 2 references to this header from the code. For the topreco_test_mt2 executable it seemed to make sense to just remove the executable outright. As it has not done anything useful in a CMake build ever. So I guess nobody actually wanted to use it for a long time by now. Still, @tdado, speak up if you disagree.

Note that RootCore/Packages.h has been completely removed from the master branch, so this should not be swept anywhere...

added sweep:ignore label

This merge request affects 3 files:

• PhysicsAnalysis/AnalysisCommon/PATCore/PATCore/TSelectorToolBase.h
• PhysicsAnalysis/TopPhys/xAOD/TopEventReconstructionTools/CMakeLists.txt
• PhysicsAnalysis/TopPhys/xAOD/TopEventReconstructionTools/util/topreco_test_mt2.cxx

Adding @goetz ,@bmondal ,@spalazzo ,@krumnack ,@omajersk ,@mvanadia ,@tdado as watchers

added 21.2 Analysis AnalysisTop review-pending-level-1 labels

Hi, thanks for preparing this. Indeed, it is perfectly fine to delete the topreco_test_mt2 executable as it has not been used for a long time.

Cheers, Tomas

Two CI jobs are triggered by 21.2 MR events: for AthDerivation with gcc62 compiler and with gcc8 for AnalysisBase and AthAnalysis projects.

• Developers and shifters need to wait for both results, sometimes for additional hour or two.

CI Result SUCCESS (hash f02afbe8)

	AnalysisBase	AthAnalysis
externals
cmake
make
required tests
optional tests

Full details available on this CI monitor view
AnalysisBase: number of compilation errors 0, warnings 0
AthAnalysis: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 23419]

CI Result SUCCESS (hash f02afbe8)

	AthDerivation
externals
cmake
make
required tests
optional tests

Full details available on this CI monitor view
AthDerivation: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-GCC62-CC7 189]

added review-approved label and removed review-pending-level-1 label

mentioned in commit 8c508b50

merged