TransformProcessType can fail, when gSystem's ProcessEvents is called from python (Apple's system version), error code is -50 (paramErr,
which (possibly) means, that process is already foreground).


git-svn-id: https://root.cern.ch/svn/root/branches/v5-34-00-patches@48479 27541ba8-7e3a-0410-8455-c3a389f83636
Fix error message.


git-svn-id: https://root.cern.ch/svn/root/branches/v5-34-00-patches@48480 27541ba8-7e3a-0410-8455-c3a389f83636