addset: use the ascending argument in _iterordered

Fix a bug where fastasc and fastdesc were iterator in the same order as
self._ascending.

mercurial/revset.py

@@ -2553,7 +2553,7 b' class _addset(abstractsmartset):'
         val2 = None
 
         choice = max
-        if self._ascending:
+        if ascending:
             choice = min
         try:
             # Consume both iterators in an ordered way until one is

tests/test-tag.t

@@ -552,6 +552,12 b' handle the loss of tags'
   $ printf '' > .hgtags
   $ hg commit -m 'delete all tags'
   created new head
+  $ hg log -r 'max(t7::)'
+  changeset:   17:ffe462b50880
+  user:        test
+  date:        Thu Jan 01 00:00:00 1970 +0000
+  summary:     Added tag t7 for changeset fd3a9e394ce3
+  
   $ hg update -r 'max(t7::)'
   2 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg merge -r tip --tool internal:tagmerge