Fix ShowGuideLIne in case of log scale: https://sft.its.cern.ch/jira/browse/ROOT-8102
Fix ShowGuideLIne in case of log scale: https://sft.its.cern.ch/jira/browse/ROOT-8102

tc3t/qoot,tc3t/qoot,tc3t/qoot,tc3t/qoot,tc3t/qoot,tc3t/qoot,tc3t/qoot,tc3t/qoot,tc3t/qoot,tc3t/qoot