from Gabriel: 

  
    - Fixed Coverity Issues 48902 - 48905  
    - speedup in TH1::GetAsymmetry (~ 10%) using RetrieveBinContent and GetBinErrorSqUnchecked


git-svn-id: https://root.cern.ch/svn/root/trunk@48420 27541ba8-7e3a-0410-8455-c3a389f83636