RFC on enhancement for org-cancel-clock with no active clock

[Adam Spiers <orgmode@adamspiers.org>]

Currently org-cancel-clock just warns 'No active clock' when there is
no active clock.  Would it make sense to extend the behaviour in that
case so that it interactively prompts whether you would like to remove
the most recently active clock entry?  This would be a nice kind of
'undo' in the case where you clock out when you actually meant to
cancel the active clock.

Thanks,
Adam