split: use field names instead of field numbers on scmutil.status

As part of my pytype adventures I want to make scmutil.status no longer a
subclass of tuple. This is part of that process.

Differential Revision: https://phab.mercurial-scm.org/D7393

hgext/split.py

@@ -152,7 +152,9 b' def dosplit(ui, repo, tr, ctx, opts):'
         scmutil.movedirstate(repo, ctx.p1())
 
     # Any modified, added, removed, deleted result means split is incomplete
-    incomplete = lambda repo: any(repo.status()[:4])
+    def incomplete(repo):
+        st = repo.status()
+        return any((st.modified, st.added, st.removed, st.deleted))
 
     # Main split loop
     while incomplete(repo):