Better redisplay of selection. Don't check zero selectionRect, as that may need redisplay when dragging. 
Better redisplay of selection. Don't check zero selectionRect, as that may need redisplay when dragging. 
WoLpH/skim,WoLpH/skim,ycaihua/skim-app,ycaihua/skim-app,WoLpH/skim,WoLpH/skim,ycaihua/skim-app,ycaihua/skim-app,WoLpH/skim,ycaihua/skim-app