Comment 22 for bug 1508110

After debugging it seems the root of the problem is in the landscape.monitor.usermonitor.UserMonitor._reset method which is called upon resynchronization, but doesn't wait for a new session ID to be available (the session ID is obtained asynchronously by the code in landscape.broker.client.BrokerClientPlugin._resynchronize).

The regression was introduced in r705.

This patch fixes the issue:

https://pastebin.canonical.com/147521/

As far as I can see, this is the only plugin affected by this kind of problem, so other plugins should be fine.