Another tree bug: Munged rendering during left scroll

[<adustman comstar net>]

I don't have a clue of how to fix this one, but I can at least demonstrate
it: Run testgtk, select tree. Create a tree with one item, depth about 20
or so. Start expanding the tree down to at least item 15-0. Then scroll
the tree all the way up to the top right. Scroll back to the left. The
tree drawing gets munged, and the slower you scroll, the more it munges.
Vertical scrolling works fine, and horizontal scrolling to the right works
find (do this at the bottom), but horizontal scrolling to the left gets
munged. This is under 1.0.1 of course. This does not appear to happen in
scrolled windows in general.

-- 
Andy Dustman                                 WW           Charles Babbage:
ComStar Communications Corp.                 BB       He never used Linux,
(770) 333-8779 | PGP KeyID=0xC72F3F1D        D?        and now, he's dead.