Fix git_nav_downstream.py when origin/master is checked out.

git_map_branches.py

 #!/usr/bin/env python
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
 """
 Provides a short mapping of all the branches in your local repo, organized by
 their upstream ('tracking branch') layout. Example:
 
 origin/master
   cool_feature
     dependent_feature
     other_dependent_feature
   other_feature
 
@@ skipping 26 matching lines @@
   elif branch_hash == cur_hash:
     color = Fore.CYAN
   else:
     color = Fore.GREEN
 
   if branch_hash == cur_hash:
     color += Style.BRIGHT
   else:
     color += Style.NORMAL
 
-  print color + "  "*depth + branch + (" *" if branch == cur else "")
+  suffix = ''
+  if cur == 'HEAD':
+    if branch_hash == cur_hash:
+      suffix = ' *'
+  elif branch == cur:
+    suffix = ' *'
+
+  print color + "  "*depth + branch + suffix
   for child in par_map.pop(branch, ()):
     print_branch(cur, cur_hash, child, branch_hashes, par_map, branch_map,
                  depth=depth+1)
 
 
 def main(argv):
   colorama.init()
   assert len(argv) == 1, "No arguments expected"
   branch_map = {}
   par_map = collections.defaultdict(list)
@@ skipping 13 matching lines @@
         if parent not in par_hashes:
           par_hashes[parent] = hash_one(parent)
         print_branch(current, current_hash, parent, par_hashes, par_map,
                      branch_map)
         break
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))