TGCocoa::DrawRectangle: I can not draw a line at y == 0 (it's clipped off), so

if I have such a rectangle, shift it 1 pixel (and reduce a height) - this fixed
toolbar buttons highlight and scrollbar.


git-svn-id: http://root.cern.ch/svn/root/trunk@43923 27541ba8-7e3a-0410-8455-c3a389f83636