get_permission_actions returns nested list

[izekia]

so such error happens:

Traceback (most recent call last):
  File "C:\Python24\lib\site-packages\trac\web\main.py", line 383, in dispatch_request
    dispatcher.dispatch(req)
  File "C:\Python24\lib\site-packages\trac\web\main.py", line 179, in dispatch
    req.perm = PermissionCache(self.env, req.authname)
  File "c:\Python24\lib\site-packages\trac\perm.py", line 263, in __init__
    self.perms = PermissionSystem(env).get_user_permissions(username)
  File "c:\Python24\lib\site-packages\trac\perm.py", line 228, in get_user_permissions
    _expand_meta(perm)
  File "c:\Python24\lib\site-packages\trac\perm.py", line 226, in _expand_meta
    [_expand_meta(perm) for perm in meta[action]]
  File "c:\Python24\lib\site-packages\trac\perm.py", line 224, in _expand_meta
    permissions[action] = True
TypeError: list objects are unhashable

[Noah Kantrowitz]

Mmm, formatey goodness.