Fix y-error bars for TGraphAsymmErrors(TH1)
Fix y-error bars for TGraphAsymmErrors(TH1)

See https://sft.its.cern.ch/jira/browse/ROOT-8969
root-mirror/root,root-mirror/root,zzxuanyuan/root,zzxuanyuan/root,karies/root,karies/root,zzxuanyuan/root,zzxuanyuan/root,zzxuanyuan/root,olifre/root,karies/root,olifre/root,zzxuanyuan/root,root-mirror/root,zzxuanyuan/root,karies/root,root-mirror/root,olifre/root,root-mirror/root,karies/root,zzxuanyuan/root,olifre/root,karies/root,zzxuanyuan/root,zzxuanyuan/root,olifre/root,zzxuanyuan/root,olifre/root,karies/root,karies/root,root-mirror/root,root-mirror/root,karies/root,karies/root,root-mirror/root,zzxuanyuan/root,olifre/root,root-mirror/root,root-mirror/root,olifre/root,root-mirror/root,olifre/root,olifre/root,karies/root,olifre/root