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. 

git-svn-id: cb3fc60f0f557b927b8032d8a94e869b6f9f230b@2104 0fceea05-a30d-0410-8a8b-80ef821fb0a1

jasongrout/skim,camillobruni/skim,camillobruni/skim,jasongrout/skim,camillobruni/skim,camillobruni/skim