crecord: update a copy-pasted comment in downarrowshiftevent()

mercurial/crecord.py

@@ -671,7 +671,7 b' class curseschunkselector(object):'
 
         currentitem = self.currentselecteditem
         nextitem = currentitem.nextitem()
-        # if there's no previous item on this level, try choosing the parent's
+        # if there's no next item on this level, try choosing the parent's
         # nextitem.
         if nextitem is None:
             try: