Temporary bandaid for top bar breaking various subreddits.

sr_pops has put certain subreddits into the top subreddit list multiple
times. This causes there to be multiple buttons in the srbar. The sort
logic in NavMenu.find_selected short circuited when the lists were of
length 1, but now that they aren't it's dying rightfully on this
attribute not existing on SubredditButton. This is a temporary patch to
help until the sr_pops issue is fixed.

r2/r2/lib/menus.py

@@ -352,7 +352,7 @@ class SubredditButton(NavButton):
                            isselected = (c.site == sr), **kw)
 
     def build(self, base_path = ''):
-        pass
+        self.bare_path = ""
 
     def is_selected(self):
         return self.isselected