if the protocol has been cleared, assume it is closed already, means …

…we can exit sooner in some cases

git-svn-id: https://xpra.org/svn/Xpra/trunk@9334 3bb7dfac-3a0b-4e04-842a-767bc560f471

src/xpra/client/client_base.py

@@ -184,7 +184,7 @@ def disconnect_and_quit(self, exit_code, reason):
         #try to tell the server we're going, then quit
         log("disconnect_and_quit(%s, %s)", exit_code, reason)
         p = self._protocol
-        if p and p._closed:
+        if p is None or p._closed:
             self.quit(exit_code)
             return
         def do_quit():