automatic reopen + retry on DatabaseModifiedError

[Eric Wong]

Hello, is there a reason Xapian does not have any way to
automatically reopen + retry on DatabaseModifiedError
exceptions? 

 (It would even be preferential to return stale data...)


I'm dealing with Search::Xapian::DatabaseModifiedError exceptions
in public-inbox[1] and going through the code to make sure there's
no more places it could fire.  But at this point, it seems like
whack-a-mole and I'm not sure if I've found everything.

[1] https://public-inbox.org/meta/20161210233543.15562-1-e@80x24.org/