dirstate._walkexplicit: indicate root as '.', not ''
'.' is the canonical way to represent the root, and it's apparently the only
transformation that normpath makes.
--- a/mercurial/dirstate.py Mon Mar 30 12:57:55 2015 -0700
+++ b/mercurial/dirstate.py Sun Mar 29 23:27:25 2015 -0700
@@ -629,7 +629,7 @@
j += 1
if not files or '.' in files:
- files = ['']
+ files = ['.']
results = dict.fromkeys(subrepos)
results['.hg'] = None