This error continues to occur in a wiki that I have created.
Running latest version up to date.
I just went through and tried each of the Map menu items on the Map tab, but no errors presented themselves.
Could you detail the steps you went through to see the error? Perhaps there is something particular about your Wiki?
Could you turn on debugging and copy and paste the presented error? It might be a different problem causing the error.
Closing this issue as I was not able to reproduce it.
If you still think this issue affects a current version, please create a new issue for that version of Moodle.