- From Valeriy:

  TImageDump:
  Add protection for cases when color doesn't exist.
  Thanks for reporting this to William Badgett at:
  http://root.cern.ch/phpBB2/viewtopic.php?p=3D16387#16387


git-svn-id: http://root.cern.ch/svn/root/trunk@16626 27541ba8-7e3a-0410-8455-c3a389f83636