#18 Missed Repainting

[Aaron Powers]

Sometimes, and only sometimes, but more and more often
as the program runs longer, repaints don't happen.

The repaints don't happen usually in the following scenario:

1) You open a sheet, say TextualViewer.
2) Go to references for TextualViewer.lineBase()
3) The TextualViewer sheet is already open, so it will jump
to TextualViewer.paintTreeWidget and paintArrow. But
when it does, it might not repaint the cursor and the lines
aroudn those fragments.
4) If you then middle-click on lineBase(), it might not repaint
the lines when it jumps to the method.

This can happen within the same sheet or two different
sheets -- the key is that the sheet is already open, and it
only happens sometimes! I think this may be a
synchronization problem and we just might need to call
repaint an extra time or something... Any ideas?