Bug 547342 attempted fix. Since scrollToRow doesn't flush layout, and since layout is what sets up the tree view, and since scrollToRow bails out early if there's no view, make sure to flush layout before calling scrollToRow. But we should really consider fixing scrollToRow instead.

content/xul/templates/tests/test_bug441785.xul

@@ -107,6 +107,7 @@ var oldtreefirstrow, oldtreecfirstrow;
 
 function nextDataSource()
 {
+  document.documentElement.getBoundingClientRect();
   var tree = document.getElementById('t');
   var treec = document.getElementById('tc');
   tree.treeBoxObject.scrollToRow(10);